Disk device

ABSTRACT

A disk drive includes: a pair of guide walls, which is arranged in the vicinity of the holder opening of a cartridge holder to define a direction in which a disk cartridge is supposed to be inserted; a first opening/closing lever, which has a first engaging portion that engages with a portion of the disk cartridge and which rotates while the disk cartridge is being inserted or ejected; and a second opening/closing lever, which has a second engaging portion that engages with another portion of the disk cartridge and which rotates while the disk cartridge is being inserted or ejected. The first and second opening/closing levers rotate so as to leave a broader gap between the first and second engaging portions than between the guide walls when the drive gets loaded with the disk cartridge, thereby opening a window in the disk cartridge.

TECHNICAL FIELD

The present invention relates to a disk drive for reading and/or writingdata from/on a disklike data storage medium such as an optical disk or amagnetic disk that is housed in a disk cartridge.

BACKGROUND ART

Various disklike read-only or rewritable storage media, includingoptical disks such as a CDs and DVDs to read and write data using alight beam, magnetic disks such as flexible disks to read and write datausing magnetism, and magneto-optical disks such as MOs and MDs to readand write data using a light beam and magnetism in combination, havealready been used extensively around the world. Among other things,DVD-RAMs, MOs and other recordable media are housed in a cartridge suchas the one disclosed in Patent Document No. 1 in order to protect thedata stored there. As used herein, a “disk cartridge” refers to acartridge in which such a disklike read-only or rewritable storagemedium is housed.

FIG. 24 schematically illustrates the structure of the disk cartridgethat is disclosed in Patent Document No. 1. As shown in FIG. 24, thedisk cartridge 100 includes a supporting base member 101 that houses aread-only or rewritable disk 10 and that forms the outer shell of thedisk cartridge 100.

The supporting base member 101 has a window 101 w on the upper and lowersurfaces thereof to allow some means for rotating the disk 10 (such as adisk motor) and a read/write means to enter the supporting base member101 and access the disk 10.

The supporting base member 101 also has inner walls for holding the disk10 rotatably with the center of the disk 10 positioned and with someclearance left with respect to the disk 10.

The disk cartridge 100 includes a shutter 103 that has been folded in aC-shape to close the window 101 w on the upper and lower surfaces of thesupporting base member 101 and to protect the data side of the disk 10to be exposed inside the window 101 w.

The shutter 103 can move parallel in the direction indicated by thearrow P in FIG. 24 and is biased by a spring so as to keep the window101 w closed unless some external force is applied thereto. Thus, thisdisk cartridge 100 is designed so as not to expose the disk 10 unlessthe external force is applied.

To perform a read/write operation on this disk cartridge 100 using adisk drive (not shown), the shutter 103 of the cartridge is moved in thedirection indicated by the arrow P and the disk 10 is exposed in orderto clamp the disk 10 and to allow a read/write means to access the disk10. In this case, as the disk cartridge 100 being inserted into the diskdrive goes in the direction indicated by the arrow Q, the notchedportion 103 a of the shutter 103 gets engaged with the protrusion 104 aof a shutter opener 104 and the shutter opener 104 is turned around thecenter of rotation 104 b in the direction indicated by the arrow R,thereby sliding the shutter in the direction indicated by the arrow P.

-   Patent Document No. 1: Japanese Patent Application Laid-Open    Publication No. 9-153264

DISCLOSURE OF INVENTION Problems to be Solved by the Invention

As in the disk cartridge disclosed in Patent Document No. 1, to get thedisk chucked and to allow the optical head to access the entire dataside of the disk, the conventional disk cartridge needs to have a windowthat runs from the center of the cartridge through its end. Also, in adisk cartridge with such a structure, the shutter moves straight withrespect to the shell of the cartridge, thus requiring a space to storethe shutter opened. That is why the size of the window depends on theoverall size of the cartridge, and therefore, it is difficult to designa small cartridge with a big window. As a result, in small portabledevices and disk video cameras in which a small cartridge is used, thesize of the optical head is limited.

In order to overcome the problems described above, the present inventionhas an object of providing an optical disk drive that is speciallydesigned for a disk cartridge that can have a big head access windoweven though its overall size is small.

Means for Solving the Problems

A disk drive according to the present invention can be loaded with adisk cartridge that houses a disk therein. The drive includes: acartridge holder for holding the disk cartridge, the holder having aholder opening, through which the disk cartridge is inserted fromoutside of the drive into the cartridge holder and ejected out of thecartridge holder; a pair of guide walls, which is arranged in thevicinity of the holder opening of the cartridge holder to define adirection in which the disk cartridge is supposed to be inserted; a diskmotor for rotating the disk that has been mounted thereon; a head forreading and/or writing information from/on the disk; a base forsupporting the head and the disk motor thereon; a first opening/closinglever, which has a first engaging portion that engages with a portion ofthe disk cartridge and which rotates while the disk cartridge is beinginserted or ejected; and a second opening/closing lever, which has asecond engaging portion that engages with another portion of the diskcartridge and which rotates while the disk cartridge is being insertedor ejected. The first and second opening/closing levers rotate and getengaged with the disk cartridge so as to leave a narrower gap betweenthe first and second engaging portions than between the guide walls whenthe disk cartridge is being inserted but to leave a broader gap betweenthe first and second engaging portions than between the guide walls whenthe drive gets loaded with the disk cartridge, thereby opening a windowin the disk cartridge so as to allow the head to access the disk andalso allow the disk motor to mount the disk.

In one preferred embodiment, the respective axes of rotation of thefirst and second opening/closing levers are located closer to the holderopening than the center of the disk is when the disk drive is loadedwith the disk cartridge.

In this particular preferred embodiment, the respective axes of rotationof the first and second opening/closing levers are arranged near theguide walls on the cartridge holder.

In another preferred embodiment, the disk cartridge includes: first andsecond disk housing portions, each of which has a space to house thedisk partially and which house the disk entirely when joined together;and a supporting base member for supporting the first and second diskhousing portions so as to allow the first and second disk housingportions to turn around their respective pivots. The first and secondengaging portions of the first and second opening/closing leversinterlock with the first and second disk housing portions, respectively,thereby turning the first and the second disk housing portions so as toopen a window in the disk cartridge being inserted.

In this particular preferred embodiment, each of the first and seconddisk housing portions of the disk cartridge includes: a notch, withwhich an associated one of the first and second engaging portions of thefirst and second opening/closing levers engages rotatably; and aninterlocking portion. The interlocking portions of the first and seconddisk housing portions engage with each other such that the first andsecond disk housing portions turn around the pivots in mutually oppositedirections and synchronously with each other.

In a specific preferred embodiment, while the disk cartridge is beinginserted or ejected, the first engaging portion gets engaged rotatablywith the notch of the first disk housing portion, thereby forming afirst link mechanism, of which the nodes are defined by the pivot of thefirst opening/closing lever, the engagement between the first engagingportion and the notch, and the pivot of the first disk housing portion.The second engaging portion also gets engaged rotatably with the notchof the second disk housing portion, thereby forming a second linkmechanism, of which the nodes are defined by the pivot of the secondopening/closing lever, the engagement between the second engagingportion and the notch, and the pivot of the second disk housing portion.The first and second disk housing portions rotate around their pivots inmutually opposite directions and synchronously with each other, therebyenabling the first and second link mechanisms to keep the insertingdirection of the disk cartridge constant.

In a more specific preferred embodiment, the guide walls are arrangedonly in the vicinity of the holder opening.

In another preferred embodiment, the disk drive further includes apositioning portion to contact with the outer edge of the disk when thedisk cartridge is loaded. The positioning portion and the disk contactwith each other, thereby positioning the center of the disk with respectto the disk motor.

In this particular preferred embodiment, the positioning portion formspart of the cartridge holder.

In a specific preferred embodiment, the first and second opening/closinglevers have guide faces in the vicinity of the first and second engagingportions. The guide faces contact with the bottom of the first andsecond disk housing portions while the disk cartridge is being insertedor ejected.

Effects of the Invention

While a disk cartridge is being inserted into the disk drive of thepresent invention, the gap between the first and second engagingportions of first and second opening/closing levers is narrower than theone between a pair of guide walls. For that reason, the first and secondengaging portions will soon contact and get engaged with the diskcartridge inserted. On the other hand, once the disk drive is loadedwith the disk cartridge, the first and second opening/closing leversrotate such that the gap between the first and second engaging portionsis wider than the gap between the guide walls. Therefore, the shuttersand housing of the disk cartridge can be opened so as to protrude out ofthe projection area of the disk cartridge when the disk housing portionsare closed. As a result, a big window can be opened. Consequently, thedisk drive of the present invention is compatible with a disk cartridgethat has relatively small outer dimensions but can still make a big headaccess window.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an exploded perspective view illustrating the structure of adisk drive as a first preferred embodiment of the present invention.

FIG. 2 is a plan view illustrating the structure of the first preferredembodiment.

FIGS. 3( a) and 3(b) are side views illustrating the structure of thefirst preferred embodiment and showing the respective positions of itscartridge holder when a disk cartridge is inserted or ejected and when aread/write operation is performed on a disk housed there, respectively.

FIG. 4 is a plan view illustrating one state of the cartridgeopening/closing mechanism of the first preferred embodiment eitherduring an opening operation or during a closing operation.

FIG. 5 is a plan view illustrating another state of the cartridgeopening/closing mechanism of the first preferred embodiment eitherduring the opening operation or during the closing operation.

FIG. 6 is a plan view illustrating another state of the cartridgeopening/closing mechanism of the first preferred embodiment eitherduring the opening operation or during the closing operation.

FIG. 7 is a plan view illustrating another state of the cartridgeopening/closing mechanism of the first preferred embodiment eitherduring the opening operation or during the closing operation.

FIG. 8 is a plan view illustrating another state of the cartridgeopening/closing mechanism of the first preferred embodiment eitherduring the opening operation or during the closing operation.

FIG. 9 is a schematic representation of link mechanisms illustrating theoperating principle of the cartridge opening/closing mechanism of thefirst preferred embodiment.

FIG. 10 is a plan view illustrating one state of a modified one of thecartridge opening/closing mechanism of the first preferred embodiment,consisting of only the second opening/closing lever, during its openingoperation.

FIG. 11 is an exploded perspective view illustrating the structure of adisk drive as a second preferred embodiment of the present invention.

FIG. 12 is a plan view illustrating the structure of the secondpreferred embodiment.

FIGS. 13( a) and 13(b) are side views illustrating the structure of thesecond preferred embodiment and showing the respective positions of itscartridge holder when a disk cartridge is inserted or ejected and when aread/write operation is performed on a disk housed there, respectively.

FIG. 14 is a plan view illustrating one state of the cartridgeopening/closing mechanism of the second preferred embodiment eitherduring an opening operation or during a closing operation.

FIG. 15 is a plan view illustrating another state of the cartridgeopening/closing mechanism of the second preferred embodiment eitherduring the opening operation or during the closing operation.

FIG. 16 is a plan view illustrating another state of the cartridgeopening/closing mechanism of the second preferred embodiment eitherduring the opening operation or during the closing operation.

FIG. 17 is a plan view illustrating another state of the cartridgeopening/closing mechanism of the second preferred embodiment eitherduring the opening operation or during the closing operation.

FIG. 18 is a plan view illustrating another state of the cartridgeopening/closing mechanism of the second preferred embodiment eitherduring the opening operation or during the closing operation.

FIGS. 19( a) and 19(b) are perspective views illustrating the generalappearance of a disk cartridge that opens and closes a window by turningits disk housing portions in two opposite directions in a situationwhere its disk housing is closed and in a situation where its diskhousing is opened, respectively.

FIGS. 20( a) and 20(b) are perspective views illustrating the generalappearance of the bottom of the disk cartridge that opens and closes awindow by turning its disk housing portions in two opposite directionsin a situation where its disk housing is closed and in a situation whereits disk housing is opened, respectively.

FIG. 21 is an exploded perspective view illustrating the structure ofsuch a disk cartridge that opens and closes a window by turning its diskhousing portions in two opposite directions.

FIGS. 22( a) and 22(b) are partial cross-sectional views of the diskcartridge shown in FIG. 19 in a situation where its disk housing isclosed and in a situation where its disk housing is opened,respectively.

FIGS. 23( a) and 23(b) are partial cross-sectional views of the diskcartridge shown in FIG. 19 in a situation where only the second lockingmember has been unlocked and in a situation where both the first andsecond locking members have been unlocked.

FIG. 24 is a plan view illustrating the general appearance of aconventional disk cartridge and one state thereof while the shutter ofthat cartridge is being opened or closed.

DESCRIPTION OF REFERENCE NUMERALS

-   10 disk-   20 traverse base-   21, 22 cartridge positioning pin-   25, 26 lever positioning pin-   30 disk motor-   40 optical head-   50 damper-   60 cartridge holder-   65 positioning portion-   150 cartridge opening/closing mechanism-   151 first opening/closing lever-   152 second opening/closing lever-   153 first lever biasing spring-   154 second lever biasing spring-   200 disk cartridge-   211 upper supporting base member-   212 lower supporting base member-   220 disk housing-   220 w window-   221 first disk housing portion-   222 second disk housing portion-   231 first locking member-   232 second locking member

BEST MODE FOR CARRYING OUT THE INVENTION

The applicant of the present application proposed a disk cartridge thathas a small overall size but can still have a big head access window inPCT International Application PCT/JP2007/059444, which has not been laidopen yet. The disk drive of the present invention is compatible withsuch a disk cartridge. Hereinafter, the structure of that disk cartridgewill be described.

FIGS. 19( a) and 19(b) are perspective views illustrating the generalappearance of a disk cartridge 200 that can be loaded into the diskdrive of the present invention as viewed from above the upper sidethereof. Specifically, FIG. 19( a) illustrates how the disk cartridge200 looks when its window is closed, and FIG. 19( b) illustrates how thedisk cartridge 200 looks when the window is opened to partially expose adisk 10 inside the cartridge 200. On the other hand, FIGS. 20( a) and20(b) are perspective views illustrating the general appearance of thedisk cartridge 200 as viewed from above the lower side thereof.Specifically, FIG. 20( a) illustrates how the disk cartridge 200 lookswhen its window is closed, and FIG. 20( b) illustrates how the diskcartridge 200 looks when the window is opened to partially expose thedisk 10 inside the cartridge 200. And FIG. 22 is an exploded perspectiveview illustrating respective members that form the disk cartridge 200.

The disk cartridge 200 includes a first disk housing portion 221, asecond disk housing portion 222 and a supporting base member 210.

The first and second disk housing portions 221 and 222 each have a spaceto house a portion of the disk 10 and form a disk housing 220 to housethe disk 10 in its entirety when joined together. More specifically,each of the first and second disk housing portions 221 and 222 has aflat baglike space to house a portion of the disk 10. And by merging thefirst and second disk housing portions 221 and 222 together with theedges of their openings fitted into each other, a space to house theentire disk 10 is produced. In the following description, the first andsecond disk housing portions 221 and 222 will sometimes be referred toherein as a “disk housing 220” collectively.

The supporting base member 210 supports the first and second diskhousing portions 221 and 222 thereon such that these housing portions221 and 222 can turn around their axes of rotation. At least a portionof the supporting base member 210 overlaps with the first and seconddisk housing portions 221 and 222 to prevent the first and second diskhousing portions 221 and 222 to move perpendicularly to the disk 10.

As shown in FIGS. 19( b) and 20(b), when the first and second diskhousing portions 221 and 222 are opened, a substantially fan-shapedwindow 220 w is made to allow a disk motor, damper and other members forrotating the disk 10 and a read/write head to approach and access thedisk 10 from outside of the disk cartridge 200.

Therefore, the first and second disk housing portions 221 and 222function not only as a housing, or an outer shell for the disk cartridge200, but also as shutters for opening and closing the window 220 w.

As shown in FIGS. 19( a) and 20(a), as viewed from over the upper orlower side of the disk cartridge 200, the disk cartridge 200 has an arcshape where the window 220 w is supposed to be opened. That is why thefirst and second disk housing portions 221 and 222 also have a curvedside surface where the window 220 w is supposed to be opened.

The supporting base member 210 includes an upper supporting base portion211 and a lower supporting base portion 212. As shown in FIG. 21, thelower supporting base portion 212 has positioning holes 215 a and 215 bto position the disk cartridge 200 on a plane that is parallel to thedisk 10 in the disk drive (not shown). Also, the lower supporting baseportion 212 has notches 212 t on both sides thereof. These notches 212 tmay be used to prevent the user from loading the disk cartridge 200upside down in a tray loading system or to engage with the diskcartridge 200 in a slot loading system, for example.

The first and second disk housing portions 221 and 222 have pivot holes221 a and 222 a, respectively, into which pivots 212 a and 212 b on thelower supporting base portion 212 are respectively inserted, therebysupporting the first and second disk housing portions 221 and 222rotatably such that these housing portions 221 and 222 can turn aroundthe pivots 212 a and 212 b, respectively.

The first and second disk housing portions 221 and 222 further haveinterlocking portions 221 b and 222 b that engage and interlock witheach other. By interlocking these interlocking portions 221 b and 222 bwith each other, the first and second disk housing portions 221 and 222can turn around their respective pivots 212 a and 212 b in mutuallyopposite directions and synchronously with each other.

Also, the first and second disk housing portions 221 and 222 havenotches 221 d and 222 d, which can be used to open or close the firstand second disk housing portions 221 and 222 externally.

A first locking member 231 and a second locking member 232 have pivotholes 231 a and 232 a, respectively, into which pivots 212 c and 212 don the lower supporting base portion 212 are inserted, so as to beattached rotatably to the lower supporting base portion 212.

The first locking member 231 includes a catching lever portion 231 bthat catches the latching portion 221 c of the first disk housingportion 221, thereby preventing the first disk housing portion 221 fromturning in the opening direction while the first and second disk housingportions 221 and 222 are closed, an opener/closer 231 c for operatingthe first locking member 231 externally, and an elastic portion 231 dthat deforms elastically under externally applied force.

Likewise, the second locking member 232 also includes a catching leverportion 232 b that catches the latching portion 222 c of the second diskhousing portion 222, thereby preventing the second disk housing portion222 from turning in the opening direction while the disk housing 220 isclosed, an opener/closer 232 c for operating the second locking member232 externally, and an elastic portion 232 d that deforms elasticallyunder externally applied force.

Furthermore, the disk cartridge 200 has unlocking slits 200 a and 200 bfor operating the first and second locking members 231 and 232 on theright- and left-hand sides thereof. The openers/closers 231 c and 232 cof the first and second locking members 231 and 232 are designed so asto protrude into the slits 200 a and 200 b, respectively, but not tostick out of the outer shell of the disk cartridge 200. Thus the personwho handles the disk cartridge 200 cannot easily press theopeners/closers 231 c and 232 c with his or her fingers. In this manner,it is possible to prevent the user from operating the locking members231 and 232 intentionally and carelessly.

Hereinafter, it will be described exactly how to open or close the diskhousing 220 of the disk cartridge 200. FIGS. 22( a) and 22(b) arepartial cross-sectional views of the disk cartridge 200 in a situationwhere the first and second disk housing portions 221 and 222 are closedand a situation where the first and second disk housing portions 221 and222 are opened, respectively.

As shown in FIG. 22( a), while the first and second disk housingportions 221 and 222 are closed, the catching lever portions 231 b and232 b of the first and second locking members 231 and 232 catch thelatching portions 221 c and 222 c of the first and second disk housingportions 221 and 222, thereby stopping the first and second disk housingportions 221 and 222 from turning in the directions indicated by thearrows 221A and 222A, respectively. In this case, the elastic portions231 d and 232 d are not deformed elastically. Also, to prevent the disk10 from rattling inside the disk cartridge 200, the inner walls of thefirst and second disk housing portions 221 and 222 have portions thatcontact with the periphery or the outer edge of the disk 10 to hold thedisk 10 firmly when the disk housing 220 is closed.

If the first and second locking members 231 and 232 are pressed down andunlocked at the same time in the state shown in FIG. 22( a) to let thefirst and second disk housing portions 221 and 222 turn in thedirections indicated by the arrows 221A and 222A, respectively, thefirst and second disk housing portions 221 and 222 are opened as shownin FIG. 22( b). In this state, the inner walls of the first and seconddisk housing portions 221 and 222 are out of contact with the disk 10and therefore the disk 10 can now take any position with respect to thesupporting base member 210 as far as the disk 10 keeps out of contactwith the inner walls. That is why the position of the disk 10 isregulated with position regulating portions 213 a, 213 b and 213 c onthe lower supporting base portion 212 and positioning portions 65provided for the disk drive.

To close the first and second disk housing portions 221 and 222, thefirst and second disk housing portions 221 and 222 are turned inopposite directions (i.e., in the directions indicated by the arrows221B and 222B, respectively) compared to the opening operation. In themeantime, the first and second locking members 231 and 232 contact withthe latching portions 221 c and 222 c of the first and second diskhousing portions 221 and 222 to rotate in the directions 231A and 232A,respectively. And when the disk housing 220 is fully closed as shown inFIG. 22( a), the first and second locking members 231 and 232 rotate inthe directions indicated by the arrows 231B and 232B, respectively,under the elastic force applied by their elastic portions 231 d and 232d. As a result, the catching lever portions 231 b and 232 b of the firstand second locking members 231 and 232 catch the latching portions 221 cand 222 c of the first and second disk housing portions 221 and 222,respectively, thereby stopping the disk housing 220 from turning. Inthis manner, the operation of closing the first and second disk housingportions 221 and 222 can get done.

In the disk cartridge 200, the overall projection area of the disk 10,the first and second disk housing portions 221, 222 and the supportingbase member 210 that is defined perpendicularly to the axis of rotationof the disk 10 is greater when the first and second disk housingportions 221 and 222 are opened as shown in FIG. 22( b) than when thefirst and second disk housing portions 221 and 222 are closed as shownin FIG. 22( a). However, since the window 220 w can have an increasedopening area, the head can be designed much more flexibly.

Next, an unlocking operation will be described. FIG. 23( a) illustratesa situation where only the second locking member 232 has been unlockedwhile the first and second disk housing portions 221 and 222 are lockedwith the first and second locking members 231 and 232. On the otherhand, FIG. 23( b) illustrates a situation where both the first andsecond locking members 231 and 232 have been unlocked while the firstand second disk housing portions 221 and 222 are locked with the firstand second locking members 231 and 232. While closed, the first andsecond disk housing portions 221 and 222 are prevented from turning inthe directions indicated by the arrows 221A and 222A, respectively, bythe first and second locking members 231 and 232 as shown in FIG. 22(a).

As shown in FIG. 23( a), if the opener/closer 232 c of the secondlocking member 232 is pressed down externally, the second locking member232 rotates in the direction indicated by the arrow 232A with itselastic portion 232 d deformed. In this state, the catching leverportion 232 b of the second locking member 232 disengages itself fromthe latching portion 222 c of the second disk housing portion 222.However, the first and second disk housing portions 221 and 222 arestill engaged with each other by their interlocking portions 221 b and222 b and the first disk housing portion 221 is still locked by thefirst locking member 231. For that reason, the first disk housingportion 221 locked prevents the second disk housing portion 222 fromrotating and never allows the user from opening the first and seconddisk housing portions 221 and 222. That is to say, even if one of thefirst and second locking members 231 and 232 were intentionally unlockedexternally, the first and second disk housing portions 221 and 222 stillcould not be opened.

However, if the openers/closers 231 c and 232 c of the first and secondlocking members 231 and 232 are externally pressed down at the sametime, the first and second locking members 231 and 232 rotate in thedirections indicated by the arrows 231A and 232A, respectively, withtheir elastic portions 231 d and 232 d deformed as shown in FIG. 23( b).In this state, the catching lever portions 231 b and 232 b of the firstand second locking members 231 and 232 disengage themselves from thelatching portions 221 c and 222 c of the first and second disk housingportions 221 and 222. As a result, the first and second disk housingportions 221 and 222 can now rotate in the directions indicated by thearrows 221A and 222A and can be opened eventually. As can be seen, onlywhen the first and second locking members 231 and 232 are unlocked atthe same time, the first and second disk housing portions 221 and 222can be opened.

The disk drive of the present invention can be loaded with the diskcartridge 200 described above to read and write information from/on thedisk 10 that is housed in the disk cartridge 200. As used herein, the“loaded” state refers to a state in which a read/write operation isready to be performed on the disk that has already been mounted on thedisk motor after the disk cartridge has been inserted into the diskdrive. Hereinafter, preferred embodiments of a disk drive according tothe present invention will be described with reference to theaccompanying drawings.

Embodiment 1

A first preferred embodiment of a disk drive according to the presentinvention will be described in detail with reference to the accompanyingdrawings.

FIGS. 1 and 2 are respectively an exploded perspective view and a planview illustrating a disk drive 501 as a first preferred embodiment ofthe present invention, which can be loaded with the disk cartridge 200.On the other hand, FIGS. 3( a) and 3(b) are side views of the disk drive501 in a situation where the disk cartridge 200 is being inserted orejected and in a situation where a read/write operation is performed onthe disk 10, respectively.

As shown in FIGS. 1 and 2, the disk drive 501 includes a traverse base20, a disk motor 30, an optical head 40 and a cartridge holder 60.

The disk motor 30 has a disk mount 30 a to mount the disk 10 and issupported on the traverse base 20. The optical head 40 is supported onthe traverse base 20 so as to move on guide pivots 41 and 42. Also, theoptical head 40 is driven by a drive source (not shown), which isarranged on the traverse base 20, along the guide pivots 41 and 42 so asto move freely in the radial direction of the disk 10 that is mounted onthe disk mount 30 a of the disk motor 30.

The optical head 40 reads and writes information from/on the disk 10.The disk drive 501 may be either a device that can perform both read andwrite operations or a read-only or write-only device.

On the traverse base 20, arranged are cartridge positioning pins 21 and22, which respectively have bearing surfaces 21 a and 22 a that willcontact with the bottom of the lower supporting base portion 212. Thecartridge positioning pins 21 and 22 are used to position the diskcartridge 200 with respect to the disk motor 30. Also arranged on thetraverse base 20 are a fixing pin 23 with a bearing surface 23 a thatwill contact with the bottom of the first disk housing portion 221 andanother fixing pin 24 with a bearing surface 24 a that will contact withthe bottom of the second disk housing portion 222. These bearingsurfaces 23 a and 24 a, as well as the bearing surfaces 21 a and 22 a ofthe cartridge positioning pins 21 and 22, determine the vertical levelof the disk cartridge 200.

The traverse base 20 also has lever positioning pins 25 and 26 that fitinto the positioning holes 151 d and 152 d of first and secondopening/closing levers 151 and 152 (to be described later), therebypositioning the first and second opening/closing levers 151 and 152 withrespect to the disk motor 30.

The disk drive 501 further includes a damper 50 and a cartridge holder60 to be loaded with the disk cartridge 200.

The damper 50 sandwiches the disk 10 between itself and the disk mount30 a of the disk motor 30, thereby clamping the disk 10 such that thedisk 10 can be rotated by the disk motor 30. The damper 50 is held by adamper supporting member (not shown) and is supported on the cartridgeholder 60.

The cartridge holder 60 holds the disk cartridge 200. The cartridgeholder 60 has a holder opening 60 s, through which the disk cartridge200 can be externally inserted into the cartridge holder 60 in thedirection indicated by the arrow 60A or through which the disk cartridge200 held in the cartridge holder 60 is ejected out of the holder 60 inthe direction indicated by the arrow 60B. The holder opening 60 s is anopening provided for the cartridge holder 60. Other than that, the diskdrive 501 may also have another opening in its housing that covers thedisk drive 501 entirely in order to insert and eject the disk cartridgethrough that opening.

In the vicinity of the holder opening 60 s of the cartridge holder 60,arranged are two guide walls 61 a and 61 b. The guide walls 61 a and 61b define the inserting and ejecting directions of the disk cartridge200. That is to say, the guide walls 61 a and 61 b contact with the sidesurfaces of the disk cartridge 200 being inserted into the cartridgeholder 60 or ejected out of the cartridge holder 60, thereby guiding thedisk cartridge 200 such that the disk cartridge 200 is inserted in thedirection indicated by the arrow 60A or ejected in the directionindicated by the arrow 60B. The guide walls 61 a and 61 b are arrangedonly in the vicinity of the holder opening 60 s.

The guide walls 61 a and 61 b include unlocking portions 62 a and 62 bthat will go inside the unlocking slits 200 a and 200 b of the diskcartridge 200 being inserted in the direction indicated by the arrow 60Aor ejected in the direction indicated by the arrow 60B, thereby pressingdown the openers/closers 231 c and 232 c of the first and second lockingmembers 231 and 232 of the disk cartridge 200.

The bottom of the cartridge holder 60 has a window 60 w to allow thedisk motor 30 and the optical head 40 to access the disk 10. Also, toprevent the cartridge positioning pins 21 and 22 and the leverpositioning pins 25 and 26 from interfering with the cartridge holder60, the bottom of the cartridge holder 60 has holes 63 a and 63 b andnotches 64 a and 64 b. The cartridge holder 60 further has a positioningportion 65 for positioning the disk 10 with respect to the center of thedisk motor 30 when the cartridge holder 60 is loaded with the diskcartridge 200.

On the holder opening 60 s of the cartridge holder 60, a notch 62 s maybe provided in order to partially expose one side surface of the diskcartridge 200 and thereby make it easier to remove the disk cartridge200 from the cartridge holder 60.

Furthermore, pivot screws 81 and 82 that are inserted into the pivotholes 20 a and 20 b of the traverse base 20 are attached to thecartridge holder 60. As a result, the cartridge holder 60 is supportedby the traverse base 20 so as to be freely rotatable in the directionsindicated by the arrows 80A and 80B.

When the disk cartridge 200 is inserted into the cartridge holder 60 inthe direction indicated by the arrow 60A or ejected out of the cartridgeholder 60 in the direction indicated by the arrow 60B, the cartridgeholder 60 is rotated θ degrees in the direction indicated by the arrow80A with respect to the traverse base 20 as shown in FIG. 3( a). In thismanner, the disk cartridge 200 can be inserted or ejected withoutinterfering with the disk motor 30, optical head 40 or variouspositioning pins on the traverse base 20.

Also, by rotating the cartridge holder 60 with respect to the traversebase 20 in the direction indicated by the arrow 80B in a situation wherethe disk cartridge 200 has been inserted into the cartridge holder 60and where the window 220 w of the disk cartridge 200 has been opened,the disk motor 30 and the optical head 40 on the traverse base 20 enterthe disk cartridge 200 through the window 220 w and the variouspositioning pins fit into their positioning holes to position the diskcartridge 200 in place as shown in FIG. 3( b). As a result, the diskdrive 501 is now loaded with the disk cartridge 200 so that a read/writeoperation is ready to be started on the disk 10.

As shown in FIG. 1, the disk drive 501 further includes a cartridgeopening/closing mechanism 150, which interlocks with portions of thedisk cartridge 200. As the disk cartridge 200 is going to be inserted orejected, the cartridge opening/closing mechanism 150 opens or closes thefirst and second disk housing portions 221 and 222. Specifically, thecartridge opening/closing mechanism 150 includes first and secondopening/closing levers 151 and 152 and first and second lever biasingsprings 153 and 154.

The first and second opening/closing levers 151 and 152 have pivot holes151 a and 152 a, respectively, and are arranged on the cartridge holder60 so as to turn around pivots 60 a and 60 b on the cartridge holder 60when the pivots 60 a and 60 b are inserted into the pivot holes 151 aand 152 a, respectively. The pivots 60 a and 60 b are arranged in thevicinity of the guide walls 61 a and 61 b, respectively.

The first and second lever biasing springs 153 and 154 are attached tothe pivots 151 b and 152 b of the first and second opening/closinglevers 151 and 152, respectively, thereby applying biasing force to thefirst opening/closing lever 151 in the direction indicated by the arrow151A and to the second opening/closing lever 152 in the directionindicated by the arrow 152A, respectively.

Also, the first opening/closing lever 151 has a first engaging portion151 c that engages with the notch 221 d of the first disk housingportion 221 and a positioning hole 151 d to receive the leverpositioning pin 25 of the traverse base 20. When the firstopening/closing lever 151 turns in the direction indicated by the arrow151A, the positioning hole 151 d positions the first opening/closinglever 151 with respect to the disk motor 30.

Likewise, the second opening/closing lever 152 has an engaging portion152 c that engages with the notch 222 d of the second disk housingportion 222 and a positioning hole 152 d to receive the leverpositioning pin 26 of the traverse base 20. When the secondopening/closing lever 152 turns in the direction indicated by the arrow152A, the positioning hole 152 d positions the second opening/closinglever 152 with respect to the disk motor 30.

The pivots 60 a and 60 b are arranged closer to the front end of thedisk drive 501 (i.e., closer to the holder opening 60 s of the cartridgeholder 60 than to the center of the disk 10 when the disk drive isloaded with the disk cartridge 200) than the engaging portions 151 c and152 c of the first and second opening/closing levers 151 and 152 are asshown in FIG. 2. Also, the pivots 60 a and 60 b are arranged in thedirection in which the guide walls 61 a and 61 b are arranged.Furthermore, the pivots 60 a and 60 b are arranged symmetrically withrespect to a plane that is defined parallel to the inserting andejecting directions of the disk cartridge 200, that passes the center ofthe disk 10 when the disk drive is loaded with the disk cartridge 200,and that intersects with the disk 10 at right angles.

Likewise, the first and second engaging portions 151 c and 152 c of thefirst and second opening/closing levers 151 and 152 are arrangedsymmetrically with respect to a plane that is defined parallel to theinserting and ejecting directions of the disk cartridge 200, that passesthe center of the disk 10 when the disk drive is loaded with the diskcartridge 200, and that intersects with the disk 10 at right angles.That is why the first and second opening/closing levers 151 and 152 arealso arranged symmetrically with respect to a plane that is definedparallel to the inserting and ejecting directions of the disk cartridge200, that passes the center of the disk 10 when the disk drive is loadedwith the disk cartridge 200, and that intersects with the disk 10 atright angles.

As shown in FIG. 2, the cartridge holder 60 has stopper portions 60 cand 60 d to stop the rotation of the first and second opening/closinglevers 151 and 152 that has been set off by the first and second leverbiasing springs 153 and 154. The first and second opening/closing levers151 and 152 are held at predetermined standby positions by these stopperportions 60 c and 60 d.

While in contact with the stopper portions 60 c and 60 d of thecartridge holder 60, the first and second opening/closing levers 151 and152 do not interfere with the lever positioning pins 25 and 26 of thetraverse base 20 as shown in FIG. 2. That is why there should be noproblem even if the cartridge holder 60 were turned as shown in FIG. 3(b) while the cartridge holder 60 is not loaded with the disk cartridge200.

Hereinafter, it will be described how the cartridge opening/closingmechanism 150 with such a configuration works. As described above, asthe disk cartridge 200 is inserted deeper into the cartridge holder 60in the direction indicated by the arrow 60A, the cartridgeopening/closing mechanism 150 opens the first and second disk housingportions 221 and 222. On the other hand, as the disk cartridge 200 isejected in the direction indicated by the arrow 60B, the cartridgeopening/closing mechanism 150 closes the first and second disk housingportions 221 and 222. It should be noted that the disk drive 501 of thispreferred embodiment has no drive mechanism for inserting and ejectingthe disk cartridge 200 automatically. That is to say, the disk cartridge200 is manually inserted in the direction indicated by the arrow 60A bythe operator. On the other hand, the disk cartridge 200 is ejected inthe direction indicated by the arrow 60B by using the biasing forceapplied by the first and second lever biasing springs 153 and 154 andthen removed manually by the operator.

First, it will be described with reference to FIGS. 4 through 8 how thecartridge opening/closing mechanism 150 opens the disk housing of thedisk cartridge 200 being inserted into the cartridge holder 60.

While the disk cartridge 200 is being inserted or ejected into/out ofthe cartridge holder 60, the cartridge holder 60 is tilted with respectto the traverse base 20 as shown in FIG. 3( a). However, the traversebase 20 has nothing to do with the operation of inserting or ejectingthe disk cartridge 200 but only the cartridge holder 60 has something todo with it. For that reason, the cartridge holder 60 and the traversebase 20 are illustrated on the same plane in FIGS. 4 through 7 for thesake of convenience. And FIG. 8 illustrates a situation where thecartridge holder 60 has been loaded with the disk cartridge 200. In thisstate, the cartridge holder 60 has been lowered and is now on a levelwith the traverse base 20 as shown in FIG. 3( b) such that the disk 10in the disk cartridge 200 is mounted on the disk mount 30 a of the diskmotor 30.

First, as shown in FIG. 4, the operator manually inserts the diskcartridge 200 through the holder opening 60 s into the cartridge holder60 in the direction indicated by the arrow 60A. In this case, the diskcartridge 200 is inserted into the cartridge holder 60 while beingguided by the guide walls 61 a and 61 b of the cartridge holder 60 inits width direction, i.e., in the direction that intersects with theinserting direction 60A at right angles.

The first and second opening/closing levers 151 and 152 contact with thestopper portions 60 c and 60 d of the cartridge holder 60, and are heldat predetermined standby positions. At this point in time, the gapbetween the first and second engaging portions 151 c and 152 c of thefirst and second opening/closing levers 151 and 152 is narrower than theone between the guide walls 61 a and 61 b. For that reason, as the diskcartridge 200 is inserted deeper, the first and second engaging portions151 c and 152 c will soon contact with the outer side surface of thefirst and second disk housing portions 221 and 222 of the disk cartridge200.

In the meantime, the unlocking portions 62 a and 62 b of the guide walls61 a and 61 b respectively go through the unlocking slits 200 a and 200b of the disk cartridge 200.

As the disk cartridge 200 is inserted even deeper than the positionshown in FIG. 4 in the direction indicated by the arrow 60A, the firstengaging portion 151 c of the first opening/closing lever 151 sooncontacts with the outer side surface of the first disk housing portion221 to overcome the biasing force applied by the lever biasing spring153 and turn around the pivot 60 a in the direction indicated by thearrow 151B as shown in FIG. 5. After that, the first opening/closinglever 151 rotates again in the direction indicated by the arrow 151Aunder the biasing force applied by the lever biasing spring 153 and thefirst engaging portion 151 c moves to a position to contact with thecatching contact face 221 f of the notch 221 d of the first disk housingportion 221.

In the same way, the engaging portion 152 c of the secondopening/closing lever 152 soon contacts with the outer side surface ofthe second disk housing portion 222 to overcome the biasing forceapplied by the lever biasing spring 154 and turn around the pivot 60 bin the direction indicated by the arrow 152B. After that, the secondopening/closing lever 152 rotates again in the direction indicated bythe arrow 152A under the biasing force applied by the lever biasingspring 154 and the second engaging portion 152 c moves to a position tocontact with the catching contact face 222 f of the notch 222 d of thesecond disk housing portion 222.

As the disk cartridge 200 is inserted even deeper than the positionshown in FIG. 5 in the direction indicated by the arrow 60A, the firstengaging portion 151 c of the first opening/closing lever 151 furthergoes on the inner wall of the notch 221 d of the first disk housingportion 221 under the biasing force applied by the lever biasing spring153 to reach the semicircular catching portion 221 e of the notch 221 dand get latched there as shown in FIG. 6. As a result, the firstopening/closing lever 151 and the first disk housing portion 221 form afirst link mechanism.

In the same way, the engaging portion 152 c of the secondopening/closing lever 152 further goes on the inner wall of the notch222 d of the second disk housing portion 222 under the biasing forceapplied by the lever biasing spring 154 to reach the semicircularcatching portion 222 e of the notch 222 d and get latched there. As aresult, the second opening/closing lever 152 and the second disk housingportion 222 form a second link mechanism.

In the meantime, the unlocking portions 62 a and 62 b press theopeners/closers 231 c and 232 c of the first and second locking members231 and 232 at the same time, thereby turning the first and secondlocking members 231 and 232 in the directions indicated by the arrows231A and 232A, respectively, while deforming their elastic portions 231d and 232 d simultaneously. As a result, the catching lever portions 231b and 232 b of the first and second locking members 231 and 232disengage themselves from the latching portions 221 c and 222 c of thefirst and second disk housing portions 221 and 222, thereby unlockingthe first and second disk housing portions 221 and 222. Consequently,the first and second disk housing portions 221 and 222 are now ready torotate in the directions indicated by the arrows 221A and 222A,respectively.

As the disk cartridge 200 is inserted even deeper than the positionshown in FIG. 6 in the direction indicated by the arrow 60A, the firstand second opening/closing levers and 152 start being rotated around thepivots 60 a and 60 b in the directions indicated by the arrows 151B and152B, respectively, by the first link mechanism formed by the firstopening/closing lever 151 and the first disk housing portion and by thesecond link mechanism formed by the second opening/closing lever 152 andthe second disk housing portion as shown in FIG. 7. Meanwhile, the firstand second disk housing portions 221 and 222 start rotating around theirpivots 212 a and 212 b in the directions indicated by the arrows 221Aand 222A, respectively.

Specifically, the lower supporting base portion 212 of the diskcartridge 200 is guided by the guide walls 61 a and 61 b in thedirections indicated by the arrows 60A and 60B. Therefore, the pivot 212a of the first disk housing portion 221 is allowed to move only in thedirections indicated by the arrows 60A and 60B. On the other hand, thepivot 60 a of the first opening/closing lever 151 is fixed. As a result,the first link mechanism is formed by the first opening/closing lever151 and the first disk housing portion 221.

The first link mechanism is formed by the first opening/closing lever151 that performs a crank operation (rotation), the pivot 212 a of thefirst disk housing portion 221 that performs a slide operation in theinserting direction (i.e., the direction indicated by the arrow 60A),and the first disk housing portion 221 that functions as a linkconnecting them. As the first opening/closing lever 151 rotates in thedirection indicated by the arrow 151B, the first disk housing portion221 rotates in the direction indicated by the arrow 221A.

Likewise, the lower supporting base portion 212 is guided by the guidewalls 61 a and 61 b in the directions indicated by the arrows 60A and60B. Therefore, the pivot 212 b of the second disk housing portion 222is allowed to move only in the directions indicated by the arrows 60Aand 60B. On the other hand, the pivot 60 a of the first opening/closinglever 151 is fixed. As a result, the second link mechanism is formed bythe second opening/closing lever 152 and the second disk housing portion222.

The second link mechanism is formed by the first opening/closing lever152 that performs a crank operation (rotation), the pivot 212 b of thesecond disk housing portion 222 that performs a slide operation in theinserting direction (i.e., the direction indicated by the arrow 60A),and the second disk housing portion 222 that functions as a linkconnecting them. As the second opening/closing lever 152 rotates in thedirection indicated by the arrow 152B, the second disk housing portion222 rotates in the direction indicated by the arrow 222A.

Thus, as the first and second opening/closing levers 151 and 152 rotatein the directions indicated by the arrows 151B and 152B, the first andsecond disk housing portions 221 and 222 rotate in the directionsindicated by the arrows 221A and 222A, respectively, using the pair oflink mechanisms (including the first and second opening/closing levers151 and 152), thereby opening the first and second disk housing portions221 and 222. In this case, the angle of rotation of the first and seconddisk housing portions 221 and 222 is determined according to how deepthe disk cartridge 200 is inserted in the direction indicated by thearrow 60A.

Also, in this case, as the first and second disk housing portions 221and 222 rotate in mutually opposite directions and synchronously witheach other at the interlocking portions 221 b and 222 b that engage witheach other, the first and second opening/closing levers 151 and 152 alsoturn in mutually opposite directions via the first and second diskhousing portions 221 and 222.

Meanwhile, the first and second opening/closing levers 151 and 152 arearranged symmetrically with respect to the direction in which the diskcartridge 200 is inserted (i.e., the direction indicated by the arrow60A). That is why the first link mechanism formed by the firstopening/closing lever 151 and the first disk housing portion 221 and thesecond link mechanism formed by the second opening/closing lever 152 andthe second disk housing portion 222 operate symmetrically with respectto the direction in which the disk cartridge 200 is inserted (i.e., thedirection indicated by the arrow 60A). Consequently, it is possible toguarantee that the disk cartridge 200 being inserted goes straight inits inserting direction.

Meanwhile, parts of the first and second opening/closing levers 151 and152 near their engaging portions 151 c and 152 c contact with, andsupport, the bottom of the first and second disk housing portions 221and 222. In this manner, while the disk cartridge 200 is being insertedin the direction indicated by the arrow 60A, the first and second diskhousing portions 221 and 222 can be guided in the height direction.

Consequently, while the disk cartridge 200 is being inserted in thedirection indicated by the arrow 60A, the first and secondopening/closing levers 151 and 152, which are arranged symmetricallywith each other, make sure that the disk cartridge 200 goes straight andalso guide the disk cartridge 200 in the height direction. As a result,the disk housing 220 can be opened with stability.

Next, as the disk cartridge 200 is inserted even deeper in the directionindicated by the arrow 60A than the position shown in FIG. 7, the diskcartridge 200 is now inserted into the cartridge holder 60 fully asshown in FIG. 8, and the first and second disk housing portions 221 and222 have rotated to form a predetermined angle between them, therebyopening the window 220 w.

At this point in time, the positioning portion 65 of the cartridgeholder 60 enters the window 220 w. Also, the position regulatingportions 213 a, 213 b and 213 c of the lower supporting base portion 212and the positioning portion 65 regulate the position of the disk 10 andposition the center of the disk 10 when the window 220 w is opened.

When the operator turns the cartridge holder 60 in the directionindicated by the arrow 80B such that the cartridge holder 60, forming apredetermined tilt angle θ with respect to the traverse base 20 as shownin FIG. 3( a), gets ready to perform a read/write operation on the disk10 as shown in FIG. 3( b), the cartridge positioning pins 21 and 22 ofthe traverse base 20 fit into the positioning holes 215 a and 215 b ofthe lower supporting base portion 212. As a result, the lower supportingbase portion 212 is positioned with respect to the traverse base 20. Atthe same time, the pivots 212 a and 212 b, around which the first andsecond disk housing portions 221 and 222 turn, are also positioned withrespect to the traverse base 20.

Consequently, the pivot 212 a of the first disk housing portion 221 thathas been movable in the directions indicated by the arrows 60A and 60Bis fixed at the predetermined position. Also, as indicated by theone-dot chain in FIG. 8, a first three-point link (i.e., a trussstructure) is formed by the pivot 60 a of the first opening/closinglever 151, the pivot 212 a of the first disk housing portion 221, andthe catching portion 221 e of the first disk housing portion 221. As aresult, the catching portion 221 e of the first disk housing portion 221has its position defined uniquely with respect to the traverse base 20.

In the same way, the pivot 212 b of the second disk housing portion 222that has been movable in the directions indicated by the arrows 60A and60B is fixed at the predetermined position. Consequently, as indicatedby the one-dot chain in FIG. 8, a second three-point link is formed bythe pivot 60 b of the second opening/closing lever 152, the pivot 212 bof the second disk housing portion 222, and the catching portion 222 eof the second disk housing portion 222. As a result, the catchingportion 222 e of the second disk housing portion 222 has its positiondefined uniquely with respect to the traverse base 20.

Thus, by positioning the lower supporting base portion 212 with respectto the traverse base 20, the angles of rotation of the first and secondopening/closing levers 151 and 152 and the positions of the axes ofrotation and the angles of rotation of the first and second disk housingportions 221 and 222 are determined uniquely by the first and secondthree-point links described above. As a result, the window 220 w isopened fully.

Nevertheless, as the first and second lever biasing springs 153 and 154apply biasing force to the first and second opening/closing levers 151and 152 in the directions indicated by the arrows 151A and 152A, thefirst and second disk housing portions 221 and 222 are positioned whilebeing biased in the closing direction. Considering a possible variationin precision between the respective members and a possible misfit of thepositioning pins, the window 220 w sometimes could become slightlynarrower and could not be opened fully.

Thus, according to this preferred embodiment, the lever positioning pins25 and 26 on the traverse base 20 are fitted into the positioning holes151 d and 152 d of the first and second opening/closing levers 151 and152, thereby positioning the first and second opening/closing levers 151and 152. In this manner, the first and second disk housing portions 221and 222 can be opened with even higher precision and a window 220 w of apredetermined size can be opened just as intended.

In this case, the gap between the first and second engaging portions 151c and 152 c of the first and second opening/closing levers 151 and 152is wider than the gap between the guide walls 61 a and 61 b. Therefore,the first and second disk housing portions 221 and 222 can be opened soas to protrude out of the projection area of the disk cartridge when thedisk housing portions are closed. As a result, a big window 220 w can beopened in the disk cartridge 200.

Also, the catching portions 221 e and 222 e of the first and second diskhousing portions 221 and 222 have regulating contact faces that contactwith the engaging portions 151 c and 152 c of the first and secondopening/closing levers 151 and 152 that are rotating in the directionsindicated by the arrows 151B and 152B, respectively. That is why whenthe first and second opening/closing levers 151 and 152 are positionedwith respect to the traverse base 20, the engaging portions 151 c and152 c of the first and second opening/closing levers 151 and 152 contactwith those regulating contact faces, thereby preventing the first andsecond disk housing portions 221 and 222 from rotating in the directionsindicated by the arrows 221B and 222B anymore. As a result, the firstand second disk housing portions 221 and 222 can be positioned just asintended without narrowing the window 220 w.

Furthermore, by getting the first and second opening/closing levers 151and 152 engaged with the lever positioning pins 25 and 26 of thetraverse base 20, respectively, the first and second disk housingportions 221 and 222 can be held by the traverse base 20 with the firstand second opening/closing levers 151 and 152. That is why even if thedisk cartridge 200 is subjected to vibrations, shocks or any otherdisturbance, the window 220 w can be kept fully opened just as intended.

The disk 10 is clamped between the disk mount 30 a of the disk motor 30and the damper 50 (not shown) to get ready to rotate. In this case, theposition regulating portions 213 a, 213 b and 213 c of the lowersupporting base portion 212 are also positioned with respect to thetraverse base 20. As a result, the position regulating portions 213 a,213 b and 213 c can provide required clearance for the disk 10. Also,the positioning portion 65 of the cartridge holder 60 is supported by,and rotatable around, the pivot screws 81 and 82 with respect to thetraverse base 20, and therefore, has been positioned accurately withrespect to the traverse base 20.

Furthermore, the bottom of the lower supporting base portion 212 issupported on the bearing surfaces 21 a and 22 a of the cartridgepositioning pins 21 and 22, while the bottom of the first and seconddisk housing portions 221 and 222 is supported on the bearing surfaces23 a and 24 a of the fixing pins 23 and 24 on the traverse base 20. Atthis point in time, parts of the first and second opening/closing levers151 and 152 near the engaging portions 151 c and 152 c thereof, whichhave been in contact with the bottom of the first and second diskhousing portions 221 and 222 and have guided the first and second diskhousing portions 221 and 222 in the height direction, are no longer incontact with the bottom of the first and second disk housing portions221 and 222.

That is to say, when a read/write operation is performed on the disk 10,the disk cartridge 200 is supported on only the four bearing surfacesdescribed above in the height direction. For that reason, the diskcartridge 200 can be accurately positioned vertically with respect tothe traverse base 20 and required clearance can be left just as intendedfor the disk 10. Optionally, springs (not shown) for pressing the diskcartridge 200 against the four bearing surfaces described above may beprovided. In that case, the disk cartridge 200 can be positioned evenmore accurately.

Also, as shown in FIG. 8, when a read/write operation is performed onthe disk 10, the unlocking portions 62 a and 62 b are out of contactwith, and do not press, the openers/closers 231 c and 232 c of the firstand second locking members 231 and 232. That is why the elastic portions231 d and 232 d of the first and second locking members 231 and 232 donot deform elastically. Consequently, even if each of the first andsecond locking members 231 and 232 is an integral member made of resin,it is still possible to prevent the elastic portions 231 d and 232 dfrom creeping.

Furthermore, when the first and second disk housing portions 221 and 222are fully opened, the pivots 60 a and 60 b around which the first andsecond opening/closing levers 151 and 152 rotate are located outside ofthe projection area of the disk cartridge 200 as shown in FIG. 8. Thatis why the members of the cartridge opening/closing mechanism 150 can bearranged efficiently without interfering with the disk cartridge 200 inthe disk drive and without expanding excessively in the width directionof the disk cartridge 200 opened. As a result, a broad area can besecured for the window 220 w, the optical head 40 can be designed moreflexibly, and the thickness and overall size of the disk drive 501 canbe cut down such that the disk drive 501 does not occupy too much space.

It should be noted that normally the disk drive 501 is designed so as toallow the disk cartridge 200 being inserted into the disk drive 501 aslightly greater stroke in the direction indicated by the arrow 60A. Forthat reason, if the disk 10 were centered only with the supporting basemember 101 as in the conventional disk cartridge 100 shown in FIG. 24,then the disk 10 being inserted would be positioned slightly deeper bythat excessive stroke, thus possibly causing some variation inpositioning accuracy depending on how deep the disk 10 has beeninserted.

However, according to this preferred embodiment, the cartridge holder 60includes the positioning portion 65 for centering the disk 10 in thedeep area of the disk drive 501. That is why even if the disk cartridge200 has been inserted to varied depths in the direction indicated by thearrow 60A, the disk 10 can still be centered accurately with respect tothe disk drive 501.

As described above, by inserting the disk cartridge 200 in the directionindicated by the arrow 60A such that the disk cartridge 200 changes itspositions from the one shown in FIG. 4 through the one shown in FIG. 8,the window 220 w of the disk cartridge 200 is fully opened and thecartridge opening/closing mechanism 150 finishes its opening operation.In addition, the disk cartridge 200 is properly loaded in the disk drive501 and a read/write operation is ready to be started on the disk 10.

Next, it will be described how the cartridge opening/closing mechanism150 performs its closing operation as the disk cartridge 200 is ejectedfrom the cartridge holder 60.

The cartridge opening/closing mechanism 150 performs its closingoperation in reverse order compared to its opening operation describedabove. That is to say, the cartridge opening/closing mechanism 150starts operating in the state shown in FIG. 8 and eventually performsthe operation of ejecting the disk cartridge 200 in the directionindicated by the arrow 60B to assume the state shown in FIG. 4. As aresult, the disk housing 220 is fully closed and the disk cartridge 200is ejected out of the drive.

Hereinafter, it will be described with reference to FIGS. 4 through 8exactly how the cartridge opening/closing mechanism 150 performs itsclosing operation.

First, as shown in FIG. 8, the operator turns the cartridge holder 60 inthe direction indicated by the arrow 80A such that the disk cartridge200 loaded properly in the disk drive 501 as shown in FIG. 3( b) isready to be inserted or ejected as shown in FIG. 3( a). Then, thecartridge positioning pins 21 and 22 are disengaged from the positioningholes 215 a and 215 b of the lower supporting base portion 212 and thelever positioning pins 25 and 26 are disengaged from the positioningholes 151 d and 152 d of the first and second opening/closing levers 151and 152. Consequently, the first and second three-point link mechanismsdescribed above are unlocked. As a result, the disk cartridge 200 is nowmovable along the guide walls 61 a and 61 b of the cartridge holder 60in the directions indicated by the arrows 60A and 60B. Also, due to thebiasing force applied by the first and second lever biasing springs 153and 154, the first and second opening/closing levers 151 and 152 startto move in the directions indicated by the arrows 151A and 152A,respectively.

Contrary to the opening operation, as the first and secondopening/closing levers 151 and 152 move in the directions indicated bythe arrows 151A and 152A, the first and second disk housing portions 221and 222 rotate in the directions indicated by the arrows 221B and 222B,respectively, using the link mechanisms including the first and secondopening/closing levers 151 and 152, thereby starting the operation ofclosing the disk housing 220.

As the first and second opening/closing levers 151 and 152 move from thepositions shown in FIG. 8 in the directions indicated by the arrows 151Aand 152A, respectively, under the biasing force applied by the first andsecond lever biasing springs 153 and 154, the disk housing 220 is closedand the disk cartridge 200 is ejected in the direction indicated by thearrow 60B as shown in FIG. 7 while being guided on the guide walls 61 aand 61 b due to the action of the link mechanisms that consist of thefirst and second opening/closing levers 151 and 152 and the first andsecond disk housing portions 221 and 222.

In this case, as in the opening operation described above, the first andsecond disk housing portions 221 and 222 rotate in mutually oppositedirections and synchronously with each other via the interlockingportions 221 b and 222 b. In addition, since the first and secondopening/closing levers 151 and 152 are arranged symmetrically withrespect to the direction in which the disk cartridge 200 is ejected(i.e., the direction indicated by the arrow 60B), the disk cartridge 200can move straight in the ejecting direction just as intended even duringthe ejecting operation.

Also, as in the opening operation described above, portions of the firstand second opening/closing levers 151 and 152 near their engagingportions 151 c and 152 c contact with, and support, the bottom of thefirst and second disk housing portions 221 and 222. In this manner,while the disk cartridge 200 is being ejected in the direction indicatedby the arrow 60B, the first and second disk housing portions 221 and 222can be guided in the height direction.

At this point in time, the first and second locking members 231 and 232of the disk cartridge 200 are out of contact with the unlocking portions62 a and 62 b. However, as the first and second disk housing portions221 and 222 rotate in the directions indicated by the arrows 221B and222B, the latching portions 221 c and 222 c of the first and second diskhousing portions 221 and 222 contact with the catching lever portions231 b and 232 b of the first and second locking members 231 and 232,thereby turning the first and second locking members 231 and 232 in thedirections indicated by the arrows 231A and 232A.

Next, as the disk cartridge 200 is ejected further forward in thedirection indicated by the arrow 60B than the position shown in FIG. 7under the biasing force applied by the first and second lever biasingsprings 153 and 154, the first and second opening/closing levers 151 and152 continue to rotate in the directions indicated by the arrows 151Aand 152A, thereby turning the first and second disk housing portions 221and 222 in the directions indicated by the arrows 221B and 222B,respectively. As a result, the window 220 w is fully closed by the diskhousing 220 as shown in FIG. 6.

At this point in time, the unlocking portions 62 a and 62 b are incontact with the openers/closers 231 c and 232 c of the first and secondlocking members 231 and 232, thus rotating the first and second lockingmembers 231 and 232 in the directions indicated by the arrows 231A and232A, respectively. That is why the latching portions 221 c and 222 c ofthe first and second disk housing portions 221 and 222 are out ofcontact with the catching lever portions 231 b and 232 b of the firstand second locking members 231 and 232 and the first and second diskhousing portions 221 and 222 are not locked.

In the state shown in FIG. 6, the first and second opening/closinglevers 151 and 152 continue to rotate in the directions indicated by thearrows 151A and 152A, respectively, under the biasing force applied bythe first and second lever biasing springs 153 and 154. Then, theengaging portions 151 c and 152 c of the first and secondopening/closing levers 151 and 152 eject the disk cartridge 200 in thedirection indicated by the arrow 60B while keeping in contact with theinner wall of the notches 221 d and 222 d of the first and second diskhousing portions 221 and 222.

Then, as shown in FIG. 5, the engaging portions 151 c and 152 c of thefirst and second opening/closing levers 151 and 152 contact with thecatching contact faces 221 f and 222 f of the notches 221 d and 222 d ofthe first and second disk housing portions 221 and 222. As a result, thedisk cartridge 200 finishes being ejected in the direction indicated bythe arrow 60B under the biasing force applied by the first and secondlever biasing springs 153 and 154.

The contact of the first and second opening/closing levers 151 and 152with the catching contact faces 221 f and 222 f prevents the diskcartridge 200 from popping out in the direction indicated by the arrow60B and dropping out of the disk drive 501 due to the biasing forceapplied by the first and second lever biasing springs 153 and 154.

At this point in time, the openers/closers 231 c and 232 c of the firstand second locking members 231 and 232 are out of contact with theunlocking portions 62 a and 62 b, respectively. Thus, under the elasticforce applied by the elastic portions 231 d and 232 d, the first andsecond locking members 231 and 232 rotate in the directions indicated bythe arrows 231B and 232B, respectively. As a result, the latchingportions 221 c and 222 c of the first and second disk housing portions221 and 222 get engaged with the catching lever portion 231 b and 232 bof the first and second locking members 231 and 232, respectively.Consequently, the first and second disk housing portions 221 and 222 arelocked so as not to rotate in the directions indicated by the arrows221A and 222A.

When the operator removes the disk cartridge 200 in the directionindicated by the arrow 60B in the state shown in FIG. 5, the first andsecond opening/closing levers 151 and 152 overcome the biasing forceapplied by the first and second lever biasing springs 153 and 154 torotate in the directions indicated by the arrows 151B and 152B.Consequently, the engaging portions 151 c and 152 c of the first andsecond opening/closing levers 151 and 152 move while sliding on thecatching contact faces 221 f and 222 f of the first and second diskhousing portions 221 and 222.

As a result, as shown in FIG. 4, the engaging portions 151 c and 152 cof the first and second opening/closing levers 151 and 152 contact withthe outer side surface of the first and second disk housing portions 221and 222 and are disengaged from the catching contact faces 221 f and 222f of the first and second disk housing portions 221 and 222.Consequently, the disk cartridge 200 is no longer held but can beremoved from the cartridge holder 60.

Finally, when the operator removes the disk cartridge 200 in thedirection indicated by the arrow 60B, the disk cartridge 200 iscompletely ejected from the cartridge holder 60 and the operation ofclosing the cartridge opening/closing mechanism 150 ends.

If the biasing force applied by the first and second lever biasingsprings 153 and 154 is great, then the disk cartridge 200 can be movedfrom the position shown in FIG. 6 to the one shown in FIG. 5 by rotatingthe first and second opening/closing levers 151 and 152 in thedirections indicated by the arrows 151A and 152A, respectively. However,if the frictional force caused by the engaging portions 151 c and 152 cof the first and second opening/closing levers 151 and 152 on the innerwall of the notches 221 d and 222 d of the first and second disk housingportions 221 and 222 is greater than the biasing force applied by thefirst and second lever biasing springs 153 and 154, the ejection of thedisk cartridge 200 in the direction indicated by the arrow 60B mayfinish at the stage shown in FIG. 6 under the biasing force applied bythe first and second lever biasing springs 153 and 154. Even so, thedisk cartridge 200 is just ejected a little less forward from thecartridge holder 60. The operator can also remove the disk cartridge 200properly by sliding the disk cartridge 200 from the position shown inFIG. 5 to the one shown in FIG. 4 in the direction indicated by thearrow 60B. In this manner, the disk cartridge 200 can be removed fromthe cartridge holder 60 with no problem at all.

As described above, by using the link mechanisms, the disk drive of thispreferred embodiment opens and closes the first and second disk housingportions 221 and 222 while the disk cartridge 200 is being inserted orejected. Hereinafter, it will be described in further detail how thoselink mechanisms work.

FIG. 9 is a schematic representation illustrating the link mechanisms toshow the principle of operation of the cartridge opening/closingmechanism 150 in the disk drive of the present invention. In FIG. 9, anycomponent having substantially the same function as the counterpartshown in FIGS. 4 through 8 is identified by the same reference numeral.It should be noted that each of those components is just shownschematically in this drawing.

Also, in FIG. 9, the first and second opening/closing levers 151 and 152and the first and second disk housing portions 221 and 222 have theirpositions shown in FIG. 6 indicated by the solid lines and theirpositions shown in FIG. 8 indicated by the dashed lines. Also, eachreference numeral with a prime such as 151′ denotes its associatedcomponent that has reached the position indicated by the dashed line inFIG. 8, and the line segment L represents a plane that is definedparallel to the directions indicated by the arrows 60A and 60B and thatincludes the axis of rotation of the disk 10.

First, as indicated by the solid lines in FIG. 9, when the engagingportion 151 c of the first opening/closing lever 151 and the catchingportion 221 e of the first disk housing portion 221 engage with eachother, the first opening/closing lever 151 and the first disk housingportion 221 form a first link mechanism. In the same way, when theengaging portion 152 c of the second opening/closing lever 152 and thecatching portion 222 e of the second disk housing portion 222 engagewith each other, the second opening/closing lever 152 and the seconddisk housing portion 222 form a second link mechanism.

The first and second opening/closing levers 151 and 152 are arrangedsymmetrically with respect to the line segment L. So are the first andsecond disk housing portions 221 and 222. That is why in FIG. 9, thefirst and second link mechanisms are also arranged symmetrically withrespect to the line segment L.

In the first and second link mechanisms, the pivots 60 a and 60 b arelocated on the cartridge holder 60, and therefore, define the pivots offixed link mechanisms. On the other hand, as the lower supporting basemember 212 is guided by the guide walls 61 a and 61 b in the directionsindicated by the arrows 60A and 60B, the pivots 212 a and 212 b of thefirst and second disk housing portions 221 and 222 define the pivots oflink mechanisms that have the freedom to move in the directionsindicated by the arrows 60A and 60B.

While the disk cartridge 200 is being inserted, the pivots 212 a and 212b move in the direction indicated by the arrow 60A to reach thepositions identified by 212 a′ and 212 b′. As the pivot 212 a moves inthe direction indicated by the arrow 60A to reach the positionidentified by 212 a′, the first opening/closing lever 151 rotates in thedirection indicated by the arrow 151B around the pivot 60 a that isfixed. As a result, the engaging portion 151 c (or the catching portion221 e) moves to the position of the engaging portion 151 c′ (or thecatching portion 221 e′). Meanwhile, the first disk housing portion 221,functioning as an interlocking link, moves in the direction indicated bythe arrow 60A while rotating in the direction indicated by the arrow221A, and the first link mechanism reaches the position indicated by thedashed lines.

Since the pivot 60 a is located closer to the front end of the diskdrive 501 (i.e., to the holder opening 60 s of the cartridge holder 60)than the engaging portion 151 c (or the catching portion 221 e) is, therotating direction (indicated by the arrow 151B) of the firstopening/closing lever 151 is the same as that (indicated by the arrow221A) of the first disk housing portion 221 while the disk cartridge 200is being inserted.

In the same way, as the pivot 212 b moves in the direction indicated bythe arrow 60A to reach the position identified by 212 b′, the secondopening/closing lever 152 rotates in the direction indicated by thearrow 152B around the pivot 60 b that is fixed. As a result, theengaging portion 152 c (or the catching portion 222 e) moves to theposition of the engaging portion 152 c′ (or the catching portion 222e′). Meanwhile, the second disk housing portion 222, functioning as aninterlocking link, moves in the direction indicated by the arrow 60Awhile rotating in the direction indicated by the arrow 222A, and thesecond link mechanism reaches the position indicated by the dashedlines.

Since the pivot 60 b is also located closer to the front end of the diskdrive 501 (i.e., to the holder opening 60 s of the cartridge holder 60)than the engaging portion 152 c (or the catching portion 222 e) is, therotating direction (indicated by the arrow 152B) of the secondopening/closing lever 152 is the same as that (indicated by the arrow222A) of the second disk housing portion 222 while the disk cartridge200 is being inserted.

In this case, the first and second disk housing portions 221 and 222,being interlocked with each other at the interlocking portions 221 b and222 b that are engaged with each other, rotate in mutually oppositedirections and synchronously with each other. That is why the anglesdefined by the first and second disk housing portions 221 and 222 withrespect to the inserting and ejecting directions in FIG. 9 satisfy α1=α2at the position indicated by the solid lines and α1′=α2′ at the positionindicated by the dashed lines. Also, since the first and second linkmechanisms are arranged symmetrically with respect to the line segmentL, the angles defined by the first and second opening/closing levers 151and 152 with respect to the directions that intersect with the insertingand ejecting directions at right angles satisfy β1=β2 at the positionindicated by the solid lines and β1′=β2′ at the position indicated bythe dashed lines.

Therefore, the first link mechanism formed by the first opening/closinglever 151 and the first disk housing portion 221 and the second linkmechanism formed by the second opening/closing lever 152 and the seconddisk housing portion 222 operate symmetrically with respect to the linesegment L while the disk cartridge 200 is being inserted (in thedirection indicated by the arrow 60A). As a result, it is possible toguarantee that the disk cartridge 200 being inserted can go straight inthe inserting direction.

While the disk cartridge 200 is being ejected, the first and secondopening/closing levers 151 and 152 rotate under the biasing forceapplied by the lever biasing springs 153 and 154. As a result, theengaging portions 151 c′ and 152 c′ (or the catching portions 221 e′ and222 e′) move toward the positions identified by 151 c and 152 c (i.e.,toward the catching portions 221 e and 222 e) in the directionsindicated by the arrows 151A and 152A, which are opposite to thedirections during the insertion operation. As the engaging portion 151c′ (or the catching portion 221 e′) moves in the direction indicated bythe arrow 151A to reach the position identified by 151 c (i.e., towardthe catching portion 221 e), the pivot 212 a moves in the directionindicated by the arrow 60B. Consequently, the first disk housing portion221, functioning as an interlocking link, moves in the directionindicated by the arrow 60B as a whole while rotating in the directionindicated by the arrow 221B, and the first link mechanism reaches theposition indicated by the solid lines.

In the same way, as the engaging portion 152 c′ (or the catching portion222 e′) moves in the direction indicated by the arrow 152A to reach theposition identified by 152 c (i.e., toward the catching portion 222 e),the pivot 212 b moves in the direction indicated by the arrow 60B.Consequently, the second disk housing portion 222, functioning as aninterlocking link, moves in the direction indicated by the arrow 60B asa whole while rotating in the direction indicated by the arrow 222B, andthe second link mechanism reaches the position indicated by the solidlines.

In this case, as in the insertion operation described above, the anglesdefined by the first and second disk housing portions 221 and 222 withrespect to the inserting and ejecting directions in FIG. 9 satisfy α1=α2at the position indicated by the solid lines and α1′=α2′ at the positionindicated by the dashed lines. Also, since the first and second linkmechanisms are arranged symmetrically with respect to the line segmentL, the angles defined by the first and second opening/closing levers 151and 152 with respect to the directions that intersect with the insertingand ejecting directions at right angles satisfy β1=β2 at the positionindicated by the solid lines and β1′=β2′ at the position indicated bythe dashed lines.

Therefore, the first link mechanism formed by the first opening/closinglever 151 and the first disk housing portion 221 and the second linkmechanism formed by the second opening/closing lever 152 and the seconddisk housing portion 222 operate symmetrically with respect to the linesegment L while the disk cartridge 200 is being ejected (in thedirection indicated by the arrow 60B). As a result, it is possible toguarantee that the disk cartridge 200 being ejected can go straight inthe ejecting direction.

As described above, the first and second link mechanisms are arrangedsymmetrically with respect to the inserting and ejecting directions ofthe disk cartridge 200 (i.e., with respect to the line segment L) andare driven synchronously with each other by way of the disk housing 220.As a result, the disk cartridge 200 can be inserted and ejected and thedisk housing 220 can be opened and closed with good stability.

In the first preferred embodiment described above, the cartridgeopening/closing mechanism 150 consists of the first and secondopening/closing levers 151 and 152. However, the first and second diskhousing portions 221 and 222 of the disk cartridge 200 can rotate inmutually opposite directions and synchronously with each other at theinterlocking portions 221 b and 222 b. That is why the first and seconddisk housing portions 221 and 222 could be opened or closed with onlyone opening/closing lever in theory.

In the disk cartridge 200, however, the disk housing 220 functioning asa housing needs to be rotated to make the window 220 w. That is why theprojection area of the disk cartridge 200 becomes greater in the openedstate than in the closed state. For that reason, the guide walls 61 aand 61 b that contact with the outer side surface of the disk cartridge200 to define the inserting and ejecting directions and positions shouldbe located nowhere but near the holder opening 60 s. Therefore, toinsert or eject the disk cartridge 200 with good stability, the diskhousing 220, which is front end of the disk cartridge 200, should beguided as will be described later.

FIG. 10 illustrates how the disk drive 501 of this preferred embodimentwould operate if the cartridge opening/closing mechanism consisted ofonly the second opening/closing lever 152 with the first opening/closinglever 151 removed.

As shown in FIG. 10, if the operator inserts the disk cartridge 200 inthe direction indicated by the arrow 60A, the engaging portion 152 c ofthe second opening/closing lever 152 soon gets engaged with the catchingportion 222 e of the second disk housing portion 222. Then, the secondopening/closing lever 152 rotates in the direction indicated by thearrow 152B, thus rotating the second disk housing portion 222 in thedirection indicated by the arrow 222A. As a result, the first diskhousing portion 221 also rotates in the direction indicated by the arrow212A because their interlocking portions 221 b and 222 b engage witheach other.

In this case, however, the disk cartridge 200 is guided in the directionindicated by the arrow 60A just by the guide walls 61 a and 61 b of thecartridge holder 60. That is why in a portion of the disk cartridge deepinside the disk drive 501, only the second disk housing portion 222 issupported by the second opening/closing lever 152.

Thus, as the operator inserts the disk cartridge 200 in the directionindicated by the arrow 60A, the second disk housing portion 222 and thesecond opening/closing lever 152 form a link mechanism, which supportsthe second disk housing portion 222 firmly and turns the second diskhousing portion 222 in the direction indicated by the arrow 222A.Meanwhile, the first disk housing portion 221 also rotates in thedirection indicated by the arrow 212A because the first disk housingportion 221 is interlocked with the second disk housing portion 222 atthe interlocking portions 221 b and 222 b. However, since there is nofirst opening/closing lever 151, the first disk housing portion 221cannot be guided sufficiently. As a result, imbalanced load is placed onthe first and second disk housing portions 221 and 222.

Consequently, the disk cartridge 200 is inserted while tilting in thedirection indicated by the arrow 200A toward the first disk housingportion 221 on which relatively light load is placed. As a result, thedisk cartridge 200 cannot be inserted properly and it is difficult toopen the disk housing 220 as intended.

Suppose the disk cartridge 200 has been inserted properly. In that case,the second disk housing portion 222, engaged with the secondopening/closing lever 152, will be positioned properly with respect tothe traverse base 20. On the other hand, the position of the first diskhousing portion 221 in the opened state is determined only by theengaging state of the interlocking portions 221 b and 222 b. As aresult, the opening area of the window 220 w would vary significantly.

This is because as the interlocking portion 221 b is arranged near thepivot 212 a, the error caused by slight misfit between the interlockingportions 221 b and 222 b will be magnified greatly at the end of thefirst disk housing portion 221. Furthermore, while the disk housing isopened, the first disk housing portion 221 is held only by beinginterlocked with the second disk housing portion 222 at the interlockingportions 221 b and 222 b, and therefore, will rotate easily in thedirection indicated by the arrow 221A or 221B when subjected to somedisturbance. This is another reason why the opening area of the windowwill vary easily.

That is why if the disk housing 220 were opened and closed with only oneopening/closing lever, then the operation of inserting or ejecting thedisk cartridge 200 would lose stability and the opening area of thewindow 220 w would vary significantly. For that reason, it is notpreferable to provide only one opening/closing lever for the cartridgeopening/closing mechanism 150 of the disk cartridge 200 that should openand close the window 220 w using the first and second disk housingportions 221 and 222 that function not only as shutters but also as ahousing.

Also, when the disk housing 220 that functions as a housing has beenrotated to make the window 220 w in the disk cartridge 200, the diskcartridge 200 will have a greater projection area than in the closedstate as shown in FIG. 8. That is why the guide width between the guidewalls 61 a and 61 b arranged near the holder opening 60 s of the diskdrive 501 becomes narrower than the width of the disk cartridge 200including the first and second disk housing portions in the openedstate.

Therefore, even if the disk cartridge 200 could not be ejected to itspredetermined position only by the biasing force applied by the firstand second opening/closing levers 151 and 152 for some reason (e.g.,some variation or failure of a member) and should be removed manually inthe direction indicated by the arrow 60B by the operator, the first andsecond disk housing portions 221 and 222 that have been opened wouldcontact with, and be closed by, the guide walls 61 a and 61 b whilepassing through the guide walls 61 a and 61 b at the holder opening. Asa result, the disk cartridge 200 could also be removed with the firstand second disk housing portions 221 and 222 closed.

In the preferred embodiment described above, the engaging portions 151 cand 152 c of the first and second opening/closing levers 151 and 152contact with the catching contact faces 221 f and 222 f of the first andsecond disk housing portions 221 and 222, respectively, therebypreventing the first and second opening/closing levers 151 and 152 fromcoming off the first and second disk housing portions 221 and 222.However, the same effect can also be achieved even if just one of thetwo opening/closing levers 151 and 152 contacts with its associatedcatching contact face 221 f or 222 f.

Also, in the preferred embodiment described above, the disk cartridge200 is positioned with the cartridge positioning pins 21 and 22 arrangedon the traverse base 20. However, the disk cartridge may also bepositioned with a different pair of pins arranged somewhere else, not onthe traverse base 20. Furthermore, the lever positioning pins 25 and 26are arranged on the traverse base 20 in the preferred embodimentdescribed above but may also be provided for any other member.

Furthermore, in the preferred embodiment described above, the engagingportions 151 c and 152 c of the first and second opening/closing levers151 and 152 engage with the catching contact faces 221 f and 222 f ofthe first and second disk housing portions 221 and 222, therebypreventing the disk cartridge 200 being ejected from popping out.However, it is also possible to prevent the disk cartridge 200 frompopping out by either providing another preventing mechanism for thedisk drive 501 or using a frictional member such as a rubber sheet.

Also, in the preferred embodiment described above, by tilting thecartridge holder 60 with respect to the traverse base 20, the diskcartridge 200 can be inserted or ejected without interfering with thedisk motor 30 or the optical head 40. However, such interference withthe disk motor 30 or the optical head 40 may also be prevented by usinga known mechanism. For example, the same effect can also be achievedeven if the disk cartridge 200 is inserted or ejected by lifting thecartridge holder 60 with respect to the traverse base 20 with these twomembers kept substantially parallel to each other or by tilting thetraverse base 20 with respect to the cartridge holder 60.

Furthermore, in the preferred embodiment described above, the diskhousing 220 is opened or closed by directly inserting or ejecting thedisk cartridge 200 into/from the cartridge holder 60. However, the sameeffect can also be achieved by adopting a loading mechanism in which adrive source is newly provided, the disk cartridge 200 is put or held ona tray, a holder or any other transporting member, and that transportingmember is inserted into, or ejected from, the disk drive.

Furthermore, in the preferred embodiment described above, the first andsecond opening/closing levers 151 and 152 are positioned with the leverpositioning pins 25 and 26 arranged on the traverse base 20, therebymaintaining a sufficiently broad area for the window 220 w. As describedabove, the opening area of the window 220 w is determined by one linkmechanism consisting of the first opening/closing lever 151 and thefirst disk housing portion 221 and the other link mechanism consistingof the second opening/closing lever 152 and the second disk housingportion 222. Optionally, to form the respective members with higherprecision and in view of possible variation in precision between thosemembers and possible misfit of the positioning pins, this area may bedefined to be large enough to provide a sufficient area even if thewindow has shrunk to its smallest size. In that case, the positioningpins 25 and 26 may be omitted.

As described above, a disk drive according to the preferred embodimentof the present invention described above can be used effectively tooperate the disk cartridge 200 that opens and closes the window 220 wwith the first and second disk housing portions 221 and 222 functioningnot only as shutters but also as a housing. Specifically, the disk driveincludes the first and second opening/closing levers 151 and 152 thatengage with their associated notches 221 d and 222 d of the first andsecond disk housing portions 221 and 222. The first and secondopening/closing levers 151 and 152 are arranged symmetrically withrespect to the directions in which the disk cartridge 200 is inserted orejected (i.e., the directions indicated by the arrows 60A and 60B) andare respectively rotated synchronously with the insertion or ejection ofthe disk cartridge 200, thereby opening or closing the first and seconddisk housing portions appropriately. As a result, it is possible toguarantee that the disk cartridge 200 being inserted or ejected can gostraight all the way with extremely high stability.

In addition, while the disk cartridge 200 is being inserted or ejected,the first and second disk housing portions 221 and 222 are firmly heldby the first and second opening/closing levers 151 and 152,respectively. Consequently, the disk cartridge 200 can still be insertedor ejected with good stability even when subjected to any disturbancesuch as vibrations or shocks.

On top of that, the first and second opening/closing levers 151 and 152are biased by the biasing springs that apply biasing force to the firstand second disk housing portions 221 and 222 in the closing direction.Thus, when the operator is inserting the disk cartridge 200, the diskhousing can be opened while giving appropriate operation load to thefirst and second opening/closing levers 151 and 152 rotating and makingthe first and second opening/closing levers 151 and 152 engage with thefirst and second disk housing portions just as intended. On the otherhand, in performing the ejection operation, under the biasing forceapplied by the biasing springs, the disk cartridge 200 can be ejectedautomatically and the first and second disk housing portions 221 and 222can be closed just as intended.

Consequently, the operability of the disk drive while the disk cartridge200 is being inserted or ejected into/from the drive (i.e., theoperability at the man-machine interface) can be controlled solelyaccording to the biasing force applied by the biasing springs. Inaddition, there is no need to provide any drive source or drivemechanism to get the disk cartridge insertion/ejection operation done.As a result, the number of members to make a disk drive can be reducedsignificantly and the weight and the cost of the disk drive can also becut down.

On top of that, by arranging the unlocking portions 62 a and 62 b on theguide walls 61 a and 61 b of the cartridge holder 60, the unlockingportions 62 a and 62 b can be positioned more accurately with theprofile of the disk cartridge 200 taken into consideration. Therefore,the first and second locking members 231 and 232 of the disk cartridge200 can be pressed just as intended and can be unlocked at the besttiming while the disk cartridge 200 is being inserted or ejected througha series of operations.

Furthermore, by arranging the cartridge opening/closing mechanism 150closer to the holder opening 60 s of the disk drive 501, the space leftfor the optical head 40 and the area in which the first and secondopening/closing levers 151 and 152 are supposed to rotate do not overlapwith each other. As a result, the optical head 40 can be designed moreflexibly. In addition, since the optical head 40 does not overlap withthe first and second opening/closing levers 151 and 152, the thicknessof the disk drive can be reduced.

Embodiment 2

Hereinafter, a second preferred embodiment of the present invention willbe described with reference to the accompanying drawings.

A disk cartridge 200′ to be loaded into the disk drive of this preferredembodiment is the same as the disk cartridge 200 that has already beendescribed with reference to FIGS. 19 through 23 except that the firstand second disk housing portions 221 and 222 of the disk cartridge 200′have no interlocking portions 221 b and 222 b. Thus, the description ofthe disk cartridge 200′ will be omitted herein. In the followingdescription of the second preferred embodiment, any member having thesame function as the counterpart of the first preferred embodimentdescribed above will be identified by the same reference numeral as theone used to identify that counterpart.

First of all, the structure of the disk drive 502 of the secondpreferred embodiment will be described with reference to FIGS. 11through 13.

FIGS. 11 and 12 are respectively an exploded perspective view and a planview illustrating the disk drive 502, which can be loaded with the diskcartridge 200′. On the other hand, FIGS. 13( a) and 13(b) are side viewsof the disk drive 502 in a situation where the disk cartridge 200′ isbeing inserted or ejected and in a situation where a read/writeoperation is performed on the disk 10, respectively.

In these drawings, any component having either quite the same function,or substantially the same function, as the counterpart of the disk drive501 of the first preferred embodiment is identified by the samereference numeral as the one used to identify that counterpart. The diskdrive 502 has the same structure as the counterpart 501 of the firstpreferred embodiment described above except that the cartridgeopening/closing mechanism 150′ of the second preferred embodiment isdesigned differently from the counterpart of the disk drive 501 of thefirst preferred embodiment. Thus, the following description of thesecond preferred embodiment will be focused on the structure andoperation of the cartridge opening/closing mechanism 150′.

Unlike the first preferred embodiment described above, the cartridgeopening/closing mechanism 150′ of this preferred embodiment includes aconnecting arm 155 that interlocks with the first and secondopening/closing levers 151 and 152 and that rotates the first and secondopening/closing levers 151 and 152 in mutually opposite directions andsynchronously with each other.

The cartridge opening/closing mechanism 150′ opens or closes the diskhousing 220 while the disk cartridge 200′ is being inserted or ejectedinto/from the cartridge holder 60 in the direction indicated by thearrow 60A or 60B. For that purpose, the cartridge opening/closingmechanism 150′ is attached to the cartridge holder 60 and includes firstand second opening/closing levers 151 and 152, first and second leverbiasing springs 153 and 154 that apply biasing force to the first andsecond opening/closing levers 151 and 152, respectively, and theconnecting arm 155 that interlocks with the first and secondopening/closing levers 151 and 152.

The first and second opening/closing levers 151 and 152 have pivot holes151 a and 152 a, respectively, and are arranged on the cartridge holder60 so as to turn around pivots 60 a and 60 b on the cartridge holder 60when the pivots 60 a and 60 b are inserted into the pivot holes 151 aand 152 a, respectively.

The first and second lever biasing springs 153 and 154 are attached tothe pivots 151 b and 152 b of the first and second opening/closinglevers 151 and 152, respectively, thereby applying biasing force to thefirst opening/closing lever 151 in the direction indicated by the arrow151A and to the second opening/closing lever 152 in the directionindicated by the arrow 152A, respectively.

Also, the first opening/closing lever 151 has a first engaging portion151 c that engages with the notch 221 d of the first disk housingportion 221 and a positioning hole 151 d to receive the leverpositioning pin 25 of the traverse base 20. When the firstopening/closing lever 151 turns in the direction indicated by the arrow151A, the positioning hole 151 d positions the first opening/closinglever 151 with respect to the disk motor 30.

Likewise, the second opening/closing lever 152 has an engaging portion152 c that engages with the notch 222 d of the second disk housingportion 222 and a positioning hole 152 d to receive the leverpositioning pin 26 of the traverse base 20. When the secondopening/closing lever 152 turns in the direction indicated by the arrow152A, the positioning hole 152 d positions the second opening/closinglever 152 with respect to the disk motor 30.

The pivots 60 a and 60 b are arranged closer to the front end of thedisk drive 502 (i.e., closer to the holder opening 60 s of the cartridgeholder 60 than to the center of the disk 10 when the disk drive isloaded with the disk cartridge 200′) than the engaging portions 151 cand 152 c of the first and second opening/closing levers 151 and 152 areas shown in FIG. 12. Also, the pivots 60 a and 60 b are arranged in thedirection in which the guide walls 61 a and 61 b are arranged.Furthermore, the pivots 60 a and 60 b are arranged symmetrically withrespect to a plane that is defined parallel to the inserting andejecting directions of the disk cartridge 200′, that passes the centerof the disk 10 when the disk drive is loaded with the disk cartridge200′, and that intersects with the disk 10 at right angles.

Likewise, the first and second engaging portions 151 c and 152 c of thefirst and second opening/closing levers 151 and 152 are arrangedsymmetrically with respect to a plane that is defined parallel to theinserting and ejecting directions of the disk cartridge 200′, thatpasses the center of the disk 10 when the disk drive is loaded with thedisk cartridge 200′, and that intersects with the disk 10 at rightangles. That is why the first and second opening/closing levers 151 and152 are also arranged symmetrically with respect to a plane that isdefined parallel to the inserting and ejecting directions of the diskcartridge 200′, that passes the center of the disk 10 when the diskdrive is loaded with the disk cartridge 200′, and that intersects withthe disk 10 at right angles.

The connecting arm 155 has interlocking grooves 155 a and 155 b thatreceive the interlocking portions 151 e and 152 e of the first andsecond opening/closing levers 151 and 152, respectively. By fittingprotrusions 155 c into guide grooves 60 e of the cartridge holder 60,the connecting arm 155 is supported on the cartridge holder 60 so as tobe movable in the directions indicated by the arrows 60A and 60B.

The interlocking grooves 155 a and 155 b are arranged symmetrically withrespect to a plane that is defined parallel to the inserting andejecting directions (i.e., the directions indicated by the arrows 60Aand 60B) and that includes the axis of rotation of the disk 10.

The connecting arm 155 is movable only in the inserting and ejectingdirections (i.e., in the directions indicated by the arrows 60A and60B). When interlocked with the connecting arm 155, the first and secondopening/closing levers 151 and 152 rotate in mutually oppositedirections and synchronously with each other with respect to thedirections in which the disk cartridge 200′ is inserted and ejected(i.e., in the directions indicated by the arrows 60A and 60B).

As shown in FIG. 12, the cartridge holder 60 has stopper portions 60 cand 60 d to stop the rotation of the first and second opening/closinglevers 151 and 152 that has been set off by the first and second leverbiasing springs 153 and 154. The first and second opening/closing levers151 and 152 are held at predetermined standby positions by these stopperportions 60 c and 60 d.

It should be noted that the first and second opening/closing levers 151and 152 rotate synchronously with each other. That is why even if onlyone stopper portion is provided, the first and second opening/closinglevers 151 and 152 can still be held at the predetermined standbypositions.

Also, since the first and second opening/closing levers 151 and 152 areinterlocked with the connecting arm 155, the same effects as the onesachieved by the stopper portions 60 c and 60 d are achievable even bybringing the connecting arm 155 into contact with the cartridge holder60.

Furthermore, as the first and second opening/closing levers 151 and 152rotate synchronously with each other, biasing force can also be appliedto the first and second opening/closing levers 151 and 152 in thedirections indicated by the arrows 151A and 152A even by using only thefirst lever biasing spring 153.

While in contact with the stopper portions 60 c and 60 d of thecartridge holder 60, the first and second opening/closing levers 151 and152 do not interfere with the lever positioning pins 25 and 26 of thetraverse base 20 as shown in FIG. 12. That is why there should be noproblem even if the cartridge holder 60 were turned as shown in FIG. 13(b) while the cartridge holder 60 is not loaded with the disk cartridge200′.

Hereinafter, it will be described how the cartridge opening/closingmechanism 150′ with such a configuration works. As described above,unlike the disk cartridge 200 of the first preferred embodiment, thedisk cartridge 200′ has no interlocking portions 221 b and 222 b in thefirst and second disk housing portions 221 and 222. That is why thefirst and second disk housing portions 221 and 222 cannot be rotatedsynchronously with each other by the disk cartridge 200′ by itself.

As the disk cartridge 200′ is inserted deeper into the cartridge holder60 in the direction indicated by the arrow 60A, the cartridgeopening/closing mechanism 150′ opens the disk housing 220. On the otherhand, as the disk cartridge 200′ is ejected in the direction indicatedby the arrow 60B, the cartridge opening/closing mechanism 150′ closesthe disk housing 220. It should be noted that the disk drive 502 of thispreferred embodiment has no drive mechanism for inserting and ejectingthe disk cartridge 200′ automatically. That is to say, the diskcartridge 200′ is manually inserted in the direction indicated by thearrow 60A by the operator. On the other hand, the disk cartridge 200 isejected in the direction indicated by the arrow 60B by using the biasingforce applied by the first and second lever biasing springs 153 and 154and then removed manually by the operator.

First, it will be described with reference to FIGS. 14 through 18 howthe cartridge opening/closing mechanism 150 opens the disk housing ofthe disk cartridge 200′ being inserted into the cartridge holder 60.

While the disk cartridge 200′ is being inserted or ejected into/out ofthe cartridge holder 60, the cartridge holder 60 is tilted with respectto the traverse base 20 as shown in FIG. 13( a). However, the traversebase 20 has nothing to do with the operation of inserting or ejectingthe disk cartridge 200′ but only the cartridge holder 60 has somethingto do with it. For that reason, the cartridge holder 60 and the traversebase 20 are illustrated on the same plane in FIGS. 14 through 17 for thesake of convenience. And FIG. 18 illustrates a situation where thecartridge holder 60 has been loaded with the disk cartridge 200′. Inthis state, the cartridge holder 60 has been lowered and is now on alevel with the traverse base 20 as shown in FIG. 13( b) such that thedisk 10 in the disk cartridge 200′ is mounted on the disk mount 30 a ofthe disk motor 30.

First, as shown in FIG. 14, the operator manually inserts the diskcartridge 200′ through the holder opening 60 s into the cartridge holder60 in the direction indicated by the arrow 60A. In this case, the diskcartridge 200′ is inserted into the cartridge holder 60 while beingguided by the guide walls 61 a and 61 b of the cartridge holder 60 inits width direction, i.e., in the direction that intersects with theinserting direction 60A at right angles.

The first and second opening/closing levers 151 and 152 contact with thestopper portions 60 c and 60 d of the cartridge holder 60, and are heldat predetermined standby positions. At this point in time, the gapbetween the first and second engaging portions 151 c and 152 c of thefirst and second opening/closing levers 151 and 152 is narrower than theone between the guide walls 61 a and 61 b. For that reason, as the diskcartridge 200′ is inserted deeper, the first and second engagingportions 151 c and 152 c will soon contact with the outer side surfaceof the first and second disk housing portions 221 and 222 of the diskcartridge 200′.

In the meantime, the unlocking portions 62 a and 62 b of the guide walls61 a and 61 b respectively go through the unlocking slits 200 a and 200b of the disk cartridge 200′.

As the disk cartridge 200′ is inserted even deeper than the positionshown in FIG. 14 in the direction indicated by the arrow 60A, the firstengaging portion 151 c of the first opening/closing lever 151 sooncontacts with the outer side surface of the first disk housing portion221 to overcome the biasing force applied by the lever biasing spring153 and turn around the pivot 60 a in the direction indicated by thearrow 151B as shown in FIG. 15. After that, the first opening/closinglever 151 rotates again in the direction indicated by the arrow 151Aunder the biasing force applied by the lever biasing spring 153 and thefirst engaging portion 151 c moves to a position to contact with thecatching contact face 221 f of the notch 221 d of the first disk housingportion 221.

In the same way, the engaging portion 152 c of the secondopening/closing lever 152 soon contacts with the outer side surface ofthe second disk housing portion 222 to overcome the biasing forceapplied by the lever biasing spring 154 and turn around the pivot 60 bin the direction indicated by the arrow 152B. After that, the secondopening/closing lever 152 rotates again in the direction indicated bythe arrow 152A under the biasing force applied by the lever biasingspring 154 and the second engaging portion 152 c moves to a position tocontact with the catching contact face 222 f of the notch 222 d of thesecond disk housing portion 222.

As the disk cartridge 200′ is inserted even deeper than the positionshown in FIG. 15 in the direction indicated by the arrow 60A, the firstengaging portion 151 c of the first opening/closing lever 151 furthergoes on the inner wall of the notch 221 d of the first disk housingportion 221 under the biasing force applied by the lever biasing spring153 to reach the semicircular catching portion 221 e of the notch 221 dand get latched there as shown in FIG. 16. As a result, the firstopening/closing lever 151 and the first disk housing portion 221 form afirst link mechanism.

In the same way, the engaging portion 152 c of the secondopening/closing lever 152 further goes on the inner wall of the notch222 d of the second disk housing portion 222 under the biasing forceapplied by the lever biasing spring 154 to reach the semicircularcatching portion 222 e of the notch 222 d and get latched there. As aresult, the second opening/closing lever 152 and the second disk housingportion 222 form a second link mechanism.

In the meantime, the unlocking portions 62 a and 62 b press theopeners/closers 231 c and 232 c of the first and second locking members231 and 232 at the same time, thereby turning the first and secondlocking members 231 and 232 in the directions indicated by the arrows231A and 232A, respectively, while deforming their elastic portions 231d and 232 d simultaneously. As a result, the catching lever portions 231b and 232 b of the first and second locking members 231 and 232disengage themselves from the latching portions 221 c and 222 c of thefirst and second disk housing portions 221 and 222, thereby unlockingthe first and second disk housing portions 221 and 222. Consequently,the first and second disk housing portions 221 and 222 are now ready torotate in the directions indicated by the arrows 221A and 222A,respectively.

As the disk cartridge 200′ is inserted even deeper than the positionshown in FIG. 16 in the direction indicated by the arrow 60A, the firstand second opening/closing levers 151 and 152 start being rotated aroundthe pivots 60 a and 60 b in the directions indicated by the arrows 151Band 152B, respectively, by the first link mechanism formed by the firstopening/closing lever 151 and the first disk housing portion 221 and bythe second link mechanism formed by the second opening/closing lever 152and the second disk housing portion 222 as shown in FIG. 17. Meanwhile,the first and second disk housing portions 221 and 222 start rotatingaround their pivots 212 a and 212 b in the directions indicated by thearrows 221A and 222A, respectively.

This can be done thanks to the action of the first and second linkmechanisms as in the first preferred embodiment described above. Thus,the first and second disk housing portions 221 and 222 rotate in thedirections indicated by the arrows 221A and 222A, respectively, usingthe pair of link mechanisms (including the first and secondopening/closing levers 151 and 152), thereby opening the disk housing220. In this case, the angle of rotation of the first and second diskhousing portions 221 and 222 is determined according to how deep thedisk cartridge 200′ is inserted in the direction indicated by the arrow60A.

In this case, the first and second opening/closing levers 151 and 152being interlocked with the connecting arm 155 rotate in mutuallyopposite directions and synchronously with each other with respect tothe direction in which the disk cartridge 200′ is inserted (i.e., thedirection indicated by the arrow 60A) unlike the first preferredembodiment described above. That is why the first link mechanism formedby the first opening/closing lever 151 and the first disk housingportion 221 and the second link mechanism formed by the secondopening/closing lever 152 and the second disk housing portion 222operate symmetrically to each other with respect to the direction inwhich the disk cartridge 200′ is inserted (i.e., the direction indicatedby the arrow 60A).

Consequently, even without providing the interlocking portions 221 b and222 b for the disk cartridge 200′, the first and second disk housingportions 221 and 222 being interlocked with the first and secondopening/closing levers 151 and 152 rotate in mutually oppositedirections and synchronously with each other. As a result, the diskcartridge 200′ can go straight in the inserting direction during theinsertion operation.

Meanwhile, parts of the first and second opening/closing levers 151 and152 near their engaging portions 151 c and 152 c contact with, andsupport, the bottom of the first and second disk housing portions 221and 222. In this manner, while the disk cartridge 200′ is being insertedin the direction indicated by the arrow 60A, the first and second diskhousing portions 221 and 222 can be guided in the height direction.

Consequently, while the disk cartridge 200′ is being inserted in thedirection indicated by the arrow 60A, the first and secondopening/closing levers 151 and 152, which are arranged symmetricallywith each other, make sure that the disk cartridge 200′ goes straightand also guide the disk cartridge 200′ in the height direction. As aresult, the disk housing 220 can be opened with stability.

Optionally, it is possible to load the disk drive 502 of this preferredembodiment with the disk cartridge 200, of which the first and seconddisk housing portions 221 and 222 interlock with each other via theinterlocking portions 221 b and 222 b as described for the firstpreferred embodiment. In that case, however, there would be two pairs ofengaging portions to be driven synchronously with each other, andtherefore, their degrees of precision and misfit should be taken intoconsideration so as to avoid mutual interference.

Next, as the disk cartridge 200′ is inserted even deeper in thedirection indicated by the arrow 60A than the position shown in FIG. 17,the disk cartridge 200′ is now inserted into the cartridge holder 60fully as shown in FIG. 18, and the first and second disk housingportions 221 and 222 have rotated to form a predetermined angle betweenthem, thereby opening the window 220 w.

At this point in time, the positioning portion 65 of the cartridgeholder 60 enters the window 220 w. Also, the position regulatingportions 213 a, 213 b and 213 c of the lower supporting base portion 212and the positioning portion 65 regulate the position of the disk 10 andposition the center of the disk 10 when the window 220 w is opened.

When the operator turns the cartridge holder 60 in the directionindicated by the arrow 80B such that the cartridge holder 60, forming apredetermined tilt angle θ with respect to the traverse base 20 as shownin FIG. 13( a), gets ready to perform a read/write operation on the disk10 as shown in FIG. 13( b), the cartridge positioning pins 21 and 22 ofthe traverse base 20 fit into the positioning holes 215 a and 215 b ofthe lower supporting base portion 212. As a result, the lower supportingbase portion 212 is positioned with respect to the traverse base 20. Atthe same time, the pivots 212 a and 212 b, around which the first andsecond disk housing portions 221 and 222 turn, are also positioned withrespect to the traverse base 20.

Consequently, the pivot 212 a of the first disk housing portion 221 thathas been movable in the directions indicated by the arrows 60A and 60Bis fixed at the predetermined position. Also, as indicated by theone-dot chain in FIG. 18, a first three-point link (i.e., a trussstructure) is formed by the pivot 60 a of the first opening/closinglever 151, the pivot 212 a of the first disk housing portion 221, andthe catching portion 221 e of the first disk housing portion 221. As aresult, the catching portion 221 e of the first disk housing portion 221has its position defined uniquely with respect to the traverse base 20.

In the same way, the pivot 212 b of the second disk housing portion 222that has been movable in the directions indicated by the arrows 60A and60B is fixed at the predetermined position. Consequently, as indicatedby the one-dot chain in FIG. 18, a second three-point link is formed bythe pivot 60 b of the second opening/closing lever 152, the pivot 212 bof the second disk housing portion 222, and the catching portion 222 eof the second disk housing portion 222. As a result, the catchingportion 222 e of the second disk housing portion 222 has its positiondefined uniquely with respect to the traverse base 20.

Thus, by positioning the lower supporting base portion 212 with respectto the traverse base 20, the angles of rotation of the first and secondopening/closing levers 151 and 152 and the positions of the axes ofrotation and the angles of rotation of the first and second disk housingportions 221 and 222 are determined uniquely by the first and secondthree-point links described above. As a result, the window 220 w isopened fully.

Nevertheless, as the first and second lever biasing springs 153 and 154apply biasing force to the first and second opening/closing levers 151and 152 in the directions indicated by the arrows 151A and 152A, thefirst and second disk housing portions 221 and 222 are positioned whilebeing biased in the closing direction. Considering a possible variationin precision between the respective members and a possible misfit of thepositioning pins, the window 220 w sometimes could become slightlynarrower and could not be opened fully.

Thus, according to this preferred embodiment, the lever positioning pins25 and 26 on the traverse base 20 are fitted into the positioning holes151 d and 152 d of the first and second opening/closing levers 151 and152, thereby positioning the first and second opening/closing levers 151and 152. In this manner, the first and second disk housing portions 221and 222 can be opened with even higher precision and a window 220 w of apredetermined size can be opened just as intended.

In this case, the gap between the first and second engaging portions 151c and 152 c of the first and second opening/closing levers 151 and 152is wider than the gap between the guide walls 61 a and 61 b. Therefore,the first and second disk housing portions 221 and 222 can be opened soas to protrude out of the projection area of the disk cartridge when thedisk housing portions are closed. As a result, a big window 220 w can beopened in the disk cartridge 200′.

Also, the catching portions 221 e and 222 e of the first and second diskhousing portions 221 and 222 have regulating contact faces that contactwith the engaging portions 151 c and 152 c of the first and secondopening/closing levers 151 and 152 that are rotating in the directionsindicated by the arrows 151B and 152B, respectively. That is why whenthe first and second opening/closing levers 151 and 152 are positionedwith respect to the traverse base 20, the engaging portions 151 c and152 c of the first and second opening/closing levers 151 and 152 contactwith those regulating contact faces, thereby preventing the first andsecond disk housing portions 221 and 222 from rotating in the directionsindicated by the arrows 221B and 222B anymore. As a result, the firstand second disk housing portions 221 and 222 can be positioned just asintended without narrowing the window 220 w.

Furthermore, by getting the first and second opening/closing levers 151and 152 engaged with the lever positioning pins 25 and 26 of thetraverse base 20, respectively, the first and second disk housingportions 221 and 222 can be held by the traverse base 20 with the firstand second opening/closing levers 151 and 152. That is why even if thedisk cartridge 200′ is subjected to vibrations, shocks or any otherdisturbance, the window 220 w can be kept fully opened just as intended.

The disk 10 is clamped between the disk mount 30 a of the disk motor 30and the damper 50 (not shown) to get ready to rotate. In this case, theposition regulating portions 213 a, 213 b and 213 c of the lowersupporting base portion 212 are also positioned with respect to thetraverse base 20. As a result, the position regulating portions 213 a,213 b and 213 c can provide required clearance for the disk 10. Also,the positioning portion 65 of the cartridge holder 60 is supported by,and rotatable around, the pivot screws 81 and 82 with respect to thetraverse base 20, and therefore, has been positioned accurately withrespect to the traverse base 20.

Furthermore, the bottom of the lower supporting base portion 212 issupported on the bearing surfaces 21 a and 22 a of the cartridgepositioning pins 21 and 22, while the bottom of the first and seconddisk housing portions 221 and 222 is supported on the bearing surfaces23 a and 24 a of the fixing pins 23 and 24 on the traverse base 20. Atthis point in time, parts of the first and second opening/closing levers151 and 152 near the engaging portions 151 c and 152 c thereof, whichhave been in contact with the bottom of the first and second diskhousing portions 221 and 222 and have guided the first and second diskhousing portions 221 and 222 in the height direction, are no longer incontact with the bottom of the first and second disk housing portions221 and 222.

That is to say, when a read/write operation is performed on the disk 10,the disk cartridge 200′ is supported on only the four bearing surfacesdescribed above in the height direction. For that reason, the diskcartridge 200′ can be accurately positioned vertically with respect tothe traverse base 20 and required clearance can be left just as intendedfor the disk 10. Optionally, springs (not shown) for pressing the diskcartridge 200′ against the four bearing surfaces described above may beprovided. In that case, the disk cartridge 200′ can be positioned evenmore accurately.

Also, as shown in FIG. 18, when a read/write operation is performed onthe disk 10, the unlocking portions 62 a and 62 b are out of contactwith, and do not press, the openers/closers 231 c and 232 c of the firstand second locking members 231 and 232. That is why the elastic portions231 d and 232 d of the first and second locking members 231 and 232 donot deform elastically. Consequently, even if each of the first andsecond locking members 231 and 232 is an integral member made of resin,it is still possible to prevent the elastic portions 231 d and 232 dfrom creeping.

Furthermore, when the first and second disk housing portions 221 and 222are fully opened, the pivots 60 a and 60 b around which the first andsecond opening/closing levers 151 and 152 rotate are located outside ofthe projection area of the disk cartridge 200′ as shown in FIG. 18. Thatis why the members of the cartridge opening/closing mechanism 150′ canbe arranged efficiently without interfering with the disk cartridge 200′in the disk drive and without expanding excessively in the widthdirection of the disk cartridge 200′ opened. As a result, a broad areacan be secured for the window 220 w, the optical head 40 can be designedmore flexibly, and the thickness and overall size of the disk drive 502can be cut down such that the disk drive 502 does not occupy too muchspace.

It should be noted that normally the disk drive 502 is designed so as toallow the disk cartridge 200′ being inserted into the disk drive 502 aslightly greater stroke in the direction indicated by the arrow 60A. Forthat reason, if the disk 10 were centered only with the supporting basemember 101 as in the conventional disk cartridge 100 shown in FIG. 24,then the disk 10 being inserted would be positioned slightly deeper bythat excessive stroke, thus possibly causing some variation inpositioning accuracy depending on how deep the disk 10 has beeninserted.

However, according to this preferred embodiment, the cartridge holder 60includes the positioning portion 65 for centering the disk 10 in thedeep area of the disk drive 502. That is why even if the disk cartridge200′ has been inserted to varied depths in the direction indicated bythe arrow 60A, the disk 10 can still be centered accurately with respectto the disk drive 502.

As described above, by inserting the disk cartridge 200′ in thedirection indicated by the arrow 60A such that the disk cartridge 200′changes its positions from the one shown in FIG. 14 through the oneshown in FIG. 18, the window 220 w of the disk cartridge 200′ is fullyopened and the cartridge opening/closing mechanism 150′ finishes itsopening operation. In addition, the disk cartridge 200′ is properlyloaded in the disk drive 502 and a read/write operation is ready to bestarted on the disk 10.

Next, it will be described how the cartridge opening/closing mechanism150′ performs its closing operation as the disk cartridge 200′ isejected from the cartridge holder 60.

The cartridge opening/closing mechanism 150′ performs its closingoperation in reverse order compared to its opening operation describedabove. That is to say, the cartridge opening/closing mechanism 150′starts operating in the state shown in FIG. 18 and eventually performsthe operation of ejecting the disk cartridge 200′ in the directionindicated by the arrow 60B to assume the state shown in FIG. 14. As aresult, the disk housing 220 is fully closed and the disk cartridge 200′is ejected out of the drive.

Hereinafter, it will be described with reference to FIGS. 14 through 18exactly how the cartridge opening/closing mechanism 150′ performs itsclosing operation.

First, as shown in FIG. 18, the operator turns the cartridge holder 60in the direction indicated by the arrow 80A such that the disk cartridge200′ loaded properly in the disk drive 502 as shown in FIG. 13( b) isready to be inserted or ejected as shown in FIG. 13( a). Then, thecartridge positioning pins 21 and 22 are disengaged from the positioningholes 215 a and 215 b of the lower supporting base portion 212 and thelever positioning pins 25 and 26 are disengaged from the positioningholes 151 d and 152 d of the first and second opening/closing levers 151and 152. Consequently, the first and second three-point link mechanismsdescribed above are unlocked. As a result, the disk cartridge 200′ isnow movable along the guide walls 61 a and 61 b of the cartridge holder60 in the directions indicated by the arrows 60A and 60B. Also, due tothe biasing force applied by the first and second lever biasing springs153 and 154, the first and second opening/closing levers 151 and 152start to move in the directions indicated by the arrows 151A and 152A,respectively.

Contrary to the opening operation, as the first and secondopening/closing levers 151 and 152 move in the directions indicated bythe arrows 151A and 152A, the first and second disk housing portions 221and 222 rotate in the directions indicated by the arrows 221B and 222B,respectively, using the link mechanisms including the first and secondopening/closing levers 151 and 152, thereby starting the operation ofclosing the disk housing 220.

As the first and second opening/closing levers 151 and 152 move from thepositions shown in FIG. 18 in the directions indicated by the arrows151A and 152A, respectively, under the biasing force applied by thefirst and second lever biasing springs 153 and 154, the disk housing 220is closed and the disk cartridge 200′ is ejected in the directionindicated by the arrow 60B as shown in FIG. 17 while being guided on theguide walls 61 a and 61 b due to the action of the link mechanisms thatconsist of the first and second opening/closing levers 151 and 152 andthe first and second disk housing portions 221 and 222.

In this case, as in the opening operation described above, the first andsecond opening/closing levers 151 and 152 being interlocked with theconnecting arm 155 rotate in mutually opposite directions andsynchronously with each other and are arranged symmetrically withrespect to the direction in which the disk cartridge 200′ is ejected(i.e., the direction indicated by the arrow 60B). Thus, the first andsecond disk housing portions 221 and 222 being interlocked with thefirst and second opening/closing levers 151 and 152 also rotate inmutually opposite directions and synchronously with each other and thedisk cartridge 200′ can move straight just as intended even during theejecting operation.

Also, as in the opening operation described above, portions of the firstand second opening/closing levers 151 and 152 near their engaginggrooves 151 c and 152 c contact with, and support, the bottom of thefirst and second disk housing portions 221 and 222. In this manner,while the disk cartridge 200′ is being ejected in the directionindicated by the arrow 60B, the first and second disk housing portions221 and 222 can be guided in the height direction.

At this point in time, the first and second locking members 231 and 232of the disk cartridge 200′ are out of contact with the unlockingportions 62 a and 62 b. However, as the first and second disk housingportions 221 and 222 rotate in the directions indicated by the arrows221B and 222B, the latching portions 221 c and 222 c of the first andsecond disk housing portions 221 and 222 contact with the catching leverportions 231 b and 232 b of the first and second locking members 231 and232, thereby turning the first and second locking members 231 and 232 inthe directions indicated by the arrows 231A and 232A.

Next, as the disk cartridge 200′ is ejected further forward in thedirection indicated by the arrow 60B than the position shown in FIG. 17under the biasing force applied by the first and second lever biasingsprings 153 and 154, the first and second opening/closing levers 151 and152 continue to rotate in the directions indicated by the arrows 151Aand 152A, thereby turning the first and second disk housing portions 221and 222 in the directions indicated by the arrows 221B and 222B,respectively. As a result, the window 220 w is fully closed by the diskhousing 220 as shown in FIG. 16.

At this point in time, the unlocking portions 62 a and 62 b are incontact with the openers/closers 231 c and 232 c of the first and secondlocking members 231 and 232, thus rotating the first and second lockingmembers 231 and 232 in the directions indicated by the arrows 231A and232A, respectively. That is why the latching portions 221 c and 222 c ofthe first and second disk housing portions 221 and 222 are out ofcontact with the catching lever portions 231 b and 232 b of the firstand second locking members 231 and 232 and the first and second diskhousing portions 221 and 222 are not locked.

In the state shown in FIG. 16, the first and second opening/closinglevers 151 and 152 continue to rotate in the directions indicated by thearrows 151A and 152A, respectively, under the biasing force applied bythe first and second lever biasing springs 153 and 154. Then, theengaging portions 151 c and 152 c of the first and secondopening/closing levers 151 and 152 eject the disk cartridge 200′ in thedirection indicated by the arrow 60B while keeping in contact with theinner wall of the notches 221 d and 222 d of the first and second diskhousing portions 221 and 222.

Then, as shown in FIG. 15, the engaging portions 151 c and 152 c of thefirst and second opening/closing levers 151 and 152 contact with thecatching contact faces 221 f and 222 f of the notches 221 d and 222 d ofthe first and second disk housing portions 221 and 222. As a result, thedisk cartridge 200′ finishes being ejected in the direction indicated bythe arrow 60B under the biasing force applied by the first and secondlever biasing springs 153 and 154.

The contact of the first and second opening/closing levers 151 and 152with the catching contact faces 221 f and 222 f prevents the diskcartridge 200′ from popping out in the direction indicated by the arrow60B and dropping out of the disk drive 502 due to the biasing forceapplied by the first and second lever biasing springs 153 and 154.

At this point in time, the openers/closers 231 c and 232 c of the firstand second locking members 231 and 232 are out of contact with theunlocking portions 62 a and 62 b, respectively. Thus, under the elasticforce applied by the elastic portions 231 d and 232 d, the first andsecond locking members 231 and 232 rotate in the directions indicated bythe arrows 231B and 232B, respectively. As a result, the latchingportions 221 c and 222 c of the first and second disk housing portions221 and 222 get engaged with the catching lever portion 231 b and 232 bof the first and second locking members 231 and 232, respectively.Consequently, the first and second disk housing portions 221 and 222 arelocked so as not to rotate in the directions indicated by the arrows221A and 222A.

When the operator removes the disk cartridge 200′ in the directionindicated by the arrow 60B in the state shown in FIG. 15, the first andsecond opening/closing levers 151 and 152 overcome the biasing forceapplied by the first and second lever biasing springs 153 and 154 torotate in the directions indicated by the arrows 151B and 152B.Consequently, the engaging portions 151 c and 152 c of the first andsecond opening/closing levers 151 and 152 move while sliding on thecatching contact faces 221 f and 222 f of the first and second diskhousing portions 221 and 222.

As a result, as shown in FIG. 14, the engaging portions 151 c and 152 cof the first and second opening/closing levers 151 and 152 contact withthe outer side surface of the first and second disk housing portions 221and 222 and are disengaged from the catching contact faces 221 f and 222f of the first and second disk housing portions 221 and 222.Consequently, the disk cartridge 200′ is no longer held but can beremoved from the cartridge holder 60.

Finally, when the operator removes the disk cartridge 200′ in thedirection indicated by the arrow 60B, the disk cartridge 200′ iscompletely ejected from the cartridge holder 60 and the operation ofclosing the cartridge opening/closing mechanism 150′ ends.

If the biasing force applied by the first and second lever biasingsprings 153 and 154 is great, then the disk cartridge 200′ can be movedfrom the position shown in FIG. 16 to the one shown in FIG. 15 byrotating the first and second opening/closing levers 151 and 152 in thedirections indicated by the arrows 151A and 152A, respectively. However,if the frictional force caused by the engaging portions 151 c and 152 cof the first and second opening/closing levers 151 and 152 on the innerwall of the notches 221 d and 222 d of the first and second disk housingportions 221 and 222 is greater than the biasing force applied by thefirst and second lever biasing springs 153 and 154, the ejection of thedisk cartridge 200′ in the direction indicated by the arrow 60B mayfinish at the stage shown in FIG. 16 under the biasing force applied bythe first and second lever biasing springs 153 and 154. Even so, thedisk cartridge 200′ is just ejected a little less forward from thecartridge holder 60. The operator can also remove the disk cartridge200′ properly by sliding the disk cartridge 200′ from the position shownin FIG. 5 to the one shown in FIG. 14 in the direction indicated by thearrow 60B. In this manner, the disk cartridge 200′ can be removed fromthe cartridge holder 60 with no problem at all.

As described above, by using link mechanisms as in the first preferredembodiment, the disk drive 502 of this preferred embodiment can open andclose the first and second disk housing portions 221 and 222 while thedisk cartridge 200′ is being inserted or ejected.

However, unlike the first preferred embodiment, the first and secondopening/closing levers 151 and 152 are driven synchronously with eachother in this preferred embodiment while being interlocked with theconnecting arm 155. In this manner, the first link mechanism formed bythe first opening/closing lever 151 and the first disk housing portion221 and the second link mechanism formed by the second opening/closinglever 152 and the second disk housing portion 222 are drivensynchronously with each other.

Thus, while the disk cartridge 200′ is being inserted or ejected, thefirst and second opening/closing levers 151 and 152 being interlockedwith the connecting arm 155 rotate in mutually opposite directions andsynchronously with each other. Consequently, as already described forthe first preferred embodiment, the angles defined by the first andsecond opening/closing levers 151 and 152 with respect to the directionsthat intersect with the inserting and ejecting directions at rightangles in FIG. 9 satisfy β1=β2 at the position indicated by the solidlines and β1′=β2′ at the position indicated by the dashed lines.Likewise, since the first and second link mechanisms are arrangedsymmetrically with respect to the line segment L, the angles defined bythe first and second disk housing portions 221 and 222 with respect tothe inserting and ejecting directions also satisfy α1=α2 at the positionindicated by the solid lines and α1′=α2′ at the position indicated bythe dashed lines.

Therefore, the first link mechanism formed by the first opening/closinglever 151 and the first disk housing portion 221 and the second linkmechanism formed by the second opening/closing lever 152 and the seconddisk housing portion 222 operate symmetrically with respect to theinserting and ejecting directions of the disk cartridge 200′ (i.e., withrespect to the line segment L). As a result, it is possible to guaranteethat the disk cartridge 200′ being inserted or ejected can go straightin the inserting or ejecting direction.

As described above, the first and second link mechanisms are arrangedsymmetrically with respect to the inserting and ejecting directions ofthe disk cartridge 200′ (i.e., with respect to the line segment L) andare driven synchronously with each other by way of the connecting arm155. As a result, the disk cartridge 200′ can be inserted and ejectedand the disk housing 220 can be opened and closed with good stability.

In the disk cartridge 200′ of the second preferred embodiment, the firstand second disk housing portions 221 and 222 are not interlocked witheach other at the interlocking portions 221 b and 222 b unlike the firstand second preferred embodiments described above. That is why the diskhousing 220 cannot be opened or closed with only one opening/closinglever. If the disk cartridge 200 inserted is compatible with the diskdrive 501 of the first preferred embodiment, however, the disk housing220 can be opened or closed with only one opening/closing lever. Butsince this operation is the same as what has already been described forthe first preferred embodiment, the description thereof will be omittedherein.

In the preferred embodiments described above, the lever positioning pins25 and 26 that position the first and second opening/closing levers 151and 152, respectively, are arranged on the traverse base 20. However, ifthe precision of fitting is increased between the first and secondopening/closing levers 151 and 152 and the connecting arm 155 andbetween the cartridge holder 60 and the connecting arm 155, the sameeffect will be achieved even by providing only one lever positioningpin.

As described above, a disk drive according to the preferred embodimentof the present invention described above can be used effectively tooperate the disk cartridge 200′ that opens and closes the window 220 wwith the first and second disk housing portions 221 and 222 functioningnot only as shutters but also as a housing. Specifically, the first andsecond opening/closing levers 151 and 152 that engage with theirassociated notches 221 d and 222 d of the first and second disk housingportions 221 and 222 are arranged symmetrically with respect to thedirections in which the disk cartridge 200′ is inserted or ejected(i.e., the directions indicated by the arrows 60A and 60B) and arerotated synchronously with the insertion or ejection of the diskcartridge 200′, thereby opening or closing the first and second diskhousing portions appropriately. As a result, it is possible to guaranteethat the disk cartridge 200′ being inserted or ejected can go straightall the way with extremely high stability.

In addition, by rotating the first and second opening/closing levers 151and 152, which are interlocked with the connecting arm 155, in mutuallyopposite directions and synchronously with each other with respect tothe inserting and ejecting directions of the disk cartridge 200′, thepresent invention can also be applied to even the disk cartridge 200′ ofwhich the first and second disk housing portions 221 and 222 do notrotate synchronously with each other.

On top of that, since the first and second opening/closing levers 151and 152 rotate synchronously with each other while being interlockedwith the connecting arm 155, only one lever biasing spring needs to beprovided to apply biasing force to the first and second opening/closinglevers 151 and 152. As a result, the number of members required can bereduced.

As described as the first and second preferred embodiments of thepresent invention, while the disk cartridge is being inserted into thedisk drive of the present invention, the gap between the first andsecond engaging portions of the first and second opening/closing leversis narrower than the one between the guide walls. For that reason, thefirst and second engaging portions will soon contact and get engagedwith the disk cartridge inserted. On the other hand, once the disk driveis loaded with the disk cartridge, the first and second opening/closinglevers rotate such that the gap between the first and second engagingportions is wider than the gap between the guide walls. Therefore, theshutters and housing of the disk cartridge can be opened so as toprotrude out of the projection area of the disk cartridge when the diskhousing portions are closed. As a result, a big window can be opened.Consequently, the disk drive of the present invention is compatible witha disk cartridge that has relatively small outer dimensions but canstill make a big head access window.

As described above, a disk drive according to the present invention canbe used effectively to operate a disk cartridge with first and seconddisk housing portions functioning not only as shutters but also as ahousing. Specifically, first and second opening/closing levers thatengage with their associated notches of the first and second diskhousing portions of the disk cartridge are arranged symmetrically withrespect to a plane including the directions in which the disk cartridgeis inserted or ejected and the axis of rotation of the disk and arerotated synchronously with the insertion or ejection of the diskcartridge, thereby opening or closing the first and second disk housingportions appropriately. On top of that, a link mechanism consisting ofthe first opening/closing lever and the first disk housing portion andanother link mechanism consisting of the second opening/closing leverand the second disk housing portion are arranged symmetrically to eachother, thereby getting the insertion and ejection operations done withextremely high stability such that the disk cartridge can go straight.Furthermore, the first and second disk housing portions can be heldfirmly by the first and second opening/closing levers and the insertionand ejection operations can also get done with as good stability asusual even when subjected to vibrations, shocks and other disturbances.

Furthermore, the pivots around which the first and secondopening/closing levers rotate are arranged outside of the projectionarea of the disk cartridge, of which the first and second disk housingportions are opened. Thus, the interference between the first and secondopening/closing levers and the disk cartridge can be avoided in the diskdrive, and the thickness of the disk drive can be reduced.

Furthermore, the cartridge opening/closing mechanism, including thefirst and second opening/closing levers, can be arranged efficientlywithout exceeding the areas defined by the maximum width of the diskcartridge, of which the first and second disk housing portions areopened. As a result, the thickness and overall size of the disk drivecan be cut down such that the disk drive does not occupy too much space,a broad area can be secured for the head access window, and the opticalhead of the disk drive can be designed more flexibly.

On top of that, a link mechanism is formed by the first opening/closinglever and the first disk housing portion and another link mechanism isformed by the second opening/closing lever and the second disk housingportion. That is why if the supporting base member is positioned with apair of positioning pins on a base when the first and second diskhousing portions are opened, a first three-point link is formed by therotation supporting portion of the first disk housing portion, the pivotof the first opening/closing lever, and the first catching portion. Onthe other hand, a second three-point link is formed by the rotationsupporting portion of the second disk housing portion, the pivot of thesecond opening/closing lever, and the second catching portion. Thus, bypositioning the supporting base portion with respect to the base, thefirst and second three-point links define the locations and angles ofall members including the opening/closing levers uniquely, get the diskcartridge loaded in its predetermined position, and eventually, thefirst and second disk housing portions can make a window of apredetermined size at a predetermined position. As a result, positioningcan get done with a reduced number of positioning portions and yet thereliability of positioning can be improved. In addition, by directlypositioning the first and second opening/closing levers with positioningpins that have been arranged on the base, the first and second diskhousing portions in the opened state can be positioned even moreaccurately.

Moreover, the first and second opening/closing levers fit into thepositioning pins arranged on the base, thereby maintaining apredetermined angle between the first and second opening/closing leverseven under some disturbance such as vibrations or shocks. As a result,even under such a condition, the window can still keep sufficientlybroad area and it is possible to prevent the disk cartridge fromcolliding against the head or disk motor.

Furthermore, by providing not only supporting portions to contact withthe respective bottoms of the first and second disk housing portionsthat function as a housing but also a bearing surface to contact withthe bottom of the supporting base member for the base that supports thedisk motor, the first and second disk housing portions can be positionedvertically and minimum required clearance to rotate the disk can be leftaccurately. As a result, the disk drive can have a reduced thicknesswith unnecessary space eliminated, the first and second disk housingportions can be held firmly when opened and the steadiness of the diskcartridge can be increased in its opened state.

What is more, the first and second opening/closing levers are providedwith biasing springs that apply biasing force to the first and seconddisk housing portions in the closing direction. Thus, when the operatorperforms the operation of inserting the disk cartridge, the first andsecond disk housing portions can be opened while being given appropriateoperation load. On the other hand, in performing the ejection operation,the disk cartridge can be ejected automatically and the first and seconddisk housing portions can be closed just as intended by utilizing thebiasing force applied by the biasing springs. Consequently, theoperability of the disk drive while the disk cartridge is being insertedor ejected into/from the drive can be controlled solely according to thebiasing force applied by the biasing springs. In addition, there is noneed to provide any drive source or drive mechanism to get the diskcartridge insertion/ejection operation done. Consequently, the number ofmembers required can be reduced significantly and the weight and thecost of the disk drive can also be cut down.

Besides, when the first and second disk housing portions are fullyclosed, the first and second engaging portions of the first and secondopening/closing levers contact with the respective catching contactfaces of the notches of the first and second disk housing portions inthe disk cartridge. Thus, it is possible to prevent the disk cartridgebeing ejected automatically from popping out of the disk drive due tothe excessive biasing force applied by the biasing springs. As a result,the disk cartridge can be removed from the disk drive safely and wouldnot drop by itself accidentally during the ejection operation.

What is more, the width of the insertion slot, through which the diskcartridge is inserted and which is defined by the guide walls, is setsubstantially equal to the minimum width of the projection area of thedisk cartridge that is defined perpendicularly to the axis of rotationof the disk. In that case, even if the disk cartridge cannot be ejectedfor some reason with the biasing force applied by the biasing springsand if the disk cartridge should be manually removed externally, thefirst and second disk housing portions that have been opened contactwith, and are closed by, the guide walls while passing through theopening. Thus, the disk cartridge can also be removed with the first andsecond disk housing portions closed. As a result, even in an emergencywhere the disk cartridge cannot be ejected automatically, the diskcartridge can still be manually ejected safely without scratching thedisk in the disk cartridge.

On top of that, by arranging unlocking portions on portions of the guidewalls, the locking members of the disk cartridge can be unlocked at thebest timing and just as intended after the disk cartridge has beeninserted and before the disk cartridge is ejected. As a result, even ifthe disk cartridge should be ejected manually as described above, thefirst and second disk housing portions can be locked just as intendedwithout breaking the locking members.

Also, after the disk cartridge has been inserted, the locking membersare not pressed, thus preventing the locking members made of resin fromcreeping.

Furthermore, by arranging the first and second opening/closing leverscloser to the holder opening of the disk drive (i.e., closer to thefront end of the drive), the space left for the head and the area inwhich the first and second opening/closing levers are supposed to rotatedo not overlap with each other. As a result, the head can be designedmore flexibly. In addition, since the head does not overlap with thefirst and second opening/closing levers, the thickness of the disk drivecan be reduced.

INDUSTRIAL APPLICABILITY

The disk cartridge of the present invention can be used effectively toread and/or write information from/on a disk housed in a disk cartridgethat is designed to perform the read/write operations by any of variousmethods including optical, magneto-optical and magnetic ones. Amongother things, the present invention is particularly effectivelyapplicable to a disk cartridge that houses a disk of a small diameter.

1. A disk drive to be loaded with a disk cartridge that houses a disktherein, the drive comprising: a cartridge holder for holding the diskcartridge, the holder having a holder opening, through which the diskcartridge is inserted from outside of the drive into the cartridgeholder and ejected out of the cartridge holder; a pair of guide walls,which is arranged in the vicinity of the holder opening of the cartridgeholder to define a direction in which the disk cartridge is supposed tobe inserted; a disk motor for rotating the disk that has been mountedthereon; a head for reading and/or writing information from/on the disk;a base for supporting the head and the disk motor thereon; a firstopening/closing lever, which has a first engaging portion that engageswith a portion of the disk cartridge and which rotates while the diskcartridge is being inserted or ejected; and a second opening/closinglever, which has a second engaging portion that engages with anotherportion of the disk cartridge and which rotates while the disk cartridgeis being inserted or ejected, wherein the first and secondopening/closing levers rotate and get engaged with the disk cartridge soas to leave a narrower gap between the first and second engagingportions than between the guide walls when the disk cartridge is beinginserted but to leave a broader gap between the first and secondengaging portions than between the guide walls when the drive getsloaded with the disk cartridge, thereby opening a window in the diskcartridge so as to allow the head to access the disk and also allow thedisk motor to mount the disk.
 2. The disk drive of claim 1, wherein therespective axes of rotation of the first and second opening/closinglevers are located closer to the holder opening than the center of thedisk is when the disk drive is loaded with the disk cartridge.
 3. Thedisk drive of claim 2, wherein the respective axes of rotation of thefirst and second opening/closing levers are arranged near the guidewalls on the cartridge holder.
 4. The disk drive of claim 3, wherein thedisk cartridge includes: first and second disk housing portions, each ofwhich has a space to house the disk partially and which house the diskentirely when joined together; and a supporting base member forsupporting the first and second disk housing portions so as to allow thefirst and second disk housing portions to turn around their respectivepivots, wherein the first and second engaging portions of the first andsecond opening/closing levers interlock with the first and second diskhousing portions, respectively, thereby turning the first and the seconddisk housing portions so as to open a window in the disk cartridge beinginserted.
 5. The disk drive of claim 4, wherein each of the first andsecond disk housing portions of the disk cartridge includes: a notch,with which an associated one of the first and second engaging portionsof the first and second opening/closing levers engages rotatably; and aninterlocking portion, wherein the interlocking portions of the first andsecond disk housing portions engage with each other such that the firstand second disk housing portions turn around the pivots in mutuallyopposite directions and synchronously with each other.
 6. The disk driveof claim 5, wherein while the disk cartridge is being inserted orejected, the first engaging portion gets engaged rotatably with thenotch of the first disk housing portion, thereby forming a first linkmechanism, of which the nodes are defined by the pivot of the firstopening/closing lever, the engagement between the first engaging portionand the notch, and the pivot of the first disk housing portion, and thesecond engaging portion also gets engaged rotatably with the notch ofthe second disk housing portion, thereby forming a second linkmechanism, of which the nodes are defined by the pivot of the secondopening/closing lever, the engagement between the second engagingportion and the notch, and the pivot of the second disk housing portion,and wherein the first and second disk housing portions rotate aroundtheir pivots in mutually opposite directions and synchronously with eachother, thereby enabling the first and second link mechanisms to keep theinserting direction of the disk cartridge constant.
 7. The disk drive ofclaim 6, wherein the guide walls are arranged only in the vicinity ofthe holder opening.
 8. The disk drive of claim 5, further comprising apositioning portion to contact with the outer edge of the disk when thedisk cartridge is loaded, wherein the positioning portion and the diskcontact with each other, thereby positioning the center of the disk withrespect to the disk motor.
 9. The disk drive of claim 8, wherein thepositioning portion forms part of the cartridge holder.
 10. The diskdrive of claim 9, wherein the first and second opening/closing levershave guide faces in the vicinity of the first and second engagingportions, the guide faces contacting with the bottom of the first andsecond disk housing portions while the disk cartridge is being insertedor ejected.